EP4611481A1

EP4611481A1 - Aerosol provision device

Info

Publication number: EP4611481A1
Application number: EP24160884.3A
Authority: EP
Inventors: Damyn Musgrave; Neil MCCARAGHER; Matthew Roberts; Karl JESSEL
Original assignee: Nicoventures Trading Ltd
Current assignee: Nicoventures Trading Ltd
Priority date: 2024-03-01
Filing date: 2024-03-01
Publication date: 2025-09-03
Also published as: WO2025180894A1

Abstract

An aerosol provision device, an aerosol provision system, and a method of controlling an aerosol provision device. The aerosol provision device comprises a heating element comprising a semiconductor material. The heating element is electrically connected to a power supply by first and second electrical connectors, so that when power is supplied to the heating element, a rate of heating in a first region adjacent the first electrical connector and/or a rate of heating in a second region adjacent the second electrical connector is, for at least an initial time duration, greater than a rate of heating in a third region between the first and second regions.

Description

Technical Field

The present disclosure relates to an aerosol provision device, an aerosol provision system, and a method of controlling an aerosol provision device.

Background

Smoking articles such as cigarettes, cigars and the like burn tobacco during use to create tobacco smoke. Attempts have been made to provide alternatives to these articles by creating products that release compounds without combusting. Examples of such products are so-called "heat not burn" products or tobacco heating devices or products, which release compounds by heating, but not burning, material. The material may be, for example, tobacco or other non-tobacco products, which may or may not contain nicotine.

Summary

From a first aspect, there is provided an aerosol provision device comprising a heating arrangement configured to heat an aerosol generating material, comprising:

a heating element comprising a semiconductor material;
wherein the heating element is electrically connected to a power supply by a first electrical connector and a second electrical connector;
wherein the heating element comprises a first region adjacent the first electrical connector, a second region adjacent the second electrical connector, and a third region between the first and second regions, wherein when power is supplied a rate of heating in the first region and/or a rate of heating in the second region is, for at least an initial time duration, greater than a rate of heating in the third region.

Optionally, the rate of heating in the first region and/or the rate of heating in the second region is greater than the rate of heating in the third region for an initial time duration of at least 0.25 seconds, or at least 0.5 seconds, or at least 1.0 seconds, when power is supplied.
Optionally, when power is supplied a temperature of the first region and/or a temperature of the second region is greater than a temperature of the third region from at least 0 seconds, or from at least 0.2 second, or at least 0.3 seconds after power is supplied, optionally up to at least 2 seconds or at least 3 seconds or at least 4 seconds, or at least 5 seconds when power is supplied.
Optionally, when power is supplied, the rate of heating in the first region and/or the second region comprises, for at least an initial time duration (at least initially), a rate of temperature increase of at least 50 degrees Celsius per second, or at least 75 degrees Celsius per second, or at least 100 degrees Celsius per second, or at least 150 degrees Celsius per second.
Optionally, when power is supplied, the first region and/or the second region reach an operating temperature for aerosol provision faster than the third region.
Optionally, the operating temperature reached is least 150 degrees Celsius, or at least 200 degrees Celsius, or at least 250 degrees Celsius.
Optionally, when power is supplied, the rate of heating in the first region adjacent the first electrical connector, for at least an initial time duration (at least initially), differs from the rate of heating in the second region adjacent the second electrical connector.
Optionally, when power is applied the rate of heating in the first region differs from the rate of heating in the second region, from at least 0 seconds, or from at least 0.1 seconds, or from at least 0.2 seconds, or from at least 0.3 seconds after power is provided, optionally up to at least 2 seconds, or at least 3 seconds, or at least 4 seconds, or at least 5 seconds after power is provided.
Optionally, the first electrical connector is formed of a different material than the second electrical connector, and/or the first electrical connector contacts the heating element with a different surface area compared to the second electrical connector.
Optionally, an amount and/or type of dopant material in the first region differs from an amount and/or type of dopant material in the second region.
Optionally, an amount and/or type of dopant material in the first region and/or second region differs from an amount and/or type of dopant material in the third region.
Optionally, the first electrical connector and/or the second electrical connector comprises a metal and forms a Schottky Barrier with the semiconductor material of the heating element.
Optionally, the semiconductor material comprises at least one of: silicon carbide or gallium nitride.
Optionally, the heating element substantially consists of semiconductor material.
Optionally, the aerosol provision device is configured to heat a consumable article.
Optionally, the aerosol provision device comprises an article receiving portion for receiving, in use, an article comprising an aerosol generating material, and the heating element is configured to heat an article received within the article receiving portion.
Optionally, the heating element is hollow and is configured to receive an article.
Optionally, the aerosol provision device has a mouth end and a distal end, and the first electrical connector contacts the heating element closer towards the mouth end of the aerosol provision device than the second electrical connector.
Optionally, when power is supplied, current is caused to flow between the first and second electrical connectors in a direction which causes a greater rate of heating in the first region adjacent the first electrical connector than the second region adjacent the second electrical connector.
Optionally, the aerosol provision device comprises a controller configured to control (select) the direction of current flow through the heating element when power is supplied to the heating element, to control a rate of heating in the first region and/or the second region of the heating element.
Optionally, the heating element is electrically connected to the power supply by one or more further electrical connectors.
Optionally, the aerosol provision device comprises a controller configured to control which of the electrical connectors power is supplied to, and/or configured to control a direction of current flow through the heating element when power is supplied to the heating element.
From another aspect there is provided an aerosol provision system comprising an aerosol provision device in accordance with the present disclosure, and an article comprising an aerosol generating medium.
From another aspect there is provided a method of controlling a heating arrangement of an aerosol provision device, the heating arrangement comprising a heating element comprising a semiconductor material, and a power supply electrically connected to the heating element by two or more electrical connectors, the method comprising:
providing power to a first electrical connector and a second electrical connector of the electrical connectors, to cause a first region of the heating element adjacent the first electrical connector and/or a second region of the heating element adjacent to the second electrical connector to heat, for at least an initial time duration, at a greater rate of heating than a third region between the first and second regions.
Optionally, the method comprises controlling (selecting) the direction of current flow through the heating element when power is supplied to the heating element, to control a rate of heating in the first region and/or the second region of the heating element.
Optionally, the first electrical connector contacts the heating element closer towards a mouth end of the aerosol provision device than the second electrical connector, and the method comprises causing current to flow between the first and second electrical connectors in a direction which causes a greater rate of heating in the first region adjacent the first electrical connector than the second region adjacent the second electrical connector.
Optionally, the method comprises subsequently reversing the direction of current flow.
Optionally, the method comprises altering the direction of current flow through the heating element to alter the rate of heating in the first region and/or the second region of the heating element.
Optionally, the method comprises selecting which electrical connectors to provide power to.
Optionally, the method comprises subsequently providing power to a different pair of electrical connectors.
From another aspect there is provided an aerosol provision device comprising a heating arrangement configured to heat a consumable article, comprising:

a heating element comprising a semiconductor material;
wherein the heating element is operably connected to a power supply by a first electrical connector and a second electrical connector;
wherein when power is supplied, heat is generated in the heating element due to a barrier effect where the first electrical connector contacts the semiconductor material of the heating element, and/or due to a barrier effect where the second electrical connector contacts the semiconductor material of the heating element.

Optionally, the first electrical connector and/or the second electrical connector comprises a metal and forms a Schottky Barrier with the semiconductor material of the heating element.
Optionally, the barrier effect causes heating in a region of the heating element adjacent to the first connector and/or a region of the heating element adjacent the second connector, and also causes heating in a region of the heating element between the first and second electrical connectors.
Optionally, the first and second electrical connectors are separated by at most 2 cm, or at most 1 cm, or at most 0.5 cm.
Optionally, the heating element has a hollow shape for receiving an article, and the first and second electrical connectors are respectively positioned towards the inside and towards the outside surface of the hollow heating element.
Optionally, the heating element is operably connected to the power supply by one or more further electrical connectors.
Optionally, the heating element is divided into a plurality of pieces, each operably connected to a power supply by a first electrical connector and a second electrical connector.
Optionally, the aerosol provision device comprises a controller configured to control (select) which of the electrical connectors power is supplied to and/or to control (select) a direction of current flow configured through the heating element when power is supplied to the heating element.
According to another aspect there is provided a method of controlling a heating arrangement of an aerosol provision device, the heating arrangement comprising a heating element comprising a semiconductor material, and a power supply electrically connected to the heating element by a two or more electrical connectors, the method comprising:
providing power to a first electrical connector and a second electrical connector of the electrical connectors, to cause heat to be generated in the heating element due to a barrier effect where the first electrical connector contacts the semiconductor material of the heating element, and/or due to a barrier effect where the second electrical connector contacts the semiconductor material of the heating element.
Optionally, the method comprises controlling which of the electrical connectors power is supplied to control a location where heat is generated due to barrier effects.
Optionally, the method comprises controlling (selecting) the direction of current flow through the heating element when power is supplied to the heating element, to control (select) a rate of heating due to a barrier effect where the first electrical connector contacts the semiconductor material of the heating element, and/or due to control (select) a rate of heating due to a barrier effect where the second electrical connector contacts the semiconductor material of the heating element.

Brief Description of the Drawings

Various embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 shows an aerosol provision system according to an embodiment of the present disclosure;
Fig. 2 shows a heating element according to an embodiment of the present disclosure;
Figs. 3A to 3D show heating arrangements according to embodiments of the present disclosure;
Figs. 4A and 4B are thermal images of a heating element in accordance with embodiments of the present disclosure;
Fig. 5 is a graph showing the change in temperature of the heating element of Figs. 4A and 4B in response to power being provided to the heating element;
Figs. 6A and 6B illustrate schematically the effect causing current flow in different directions across a heating element in embodiments of the present disclosure;
Figs. 7A to 7D show further heating arrangements according to embodiments of the present disclosure;
Figs. 8A and 8B show further heating arrangements according to embodiments of the present disclosure;
Fig. 9 is a flowchart showing steps for controlling a heating arrangement in embodiments of the present disclosure.

Detailed description

Aspects and features of certain examples and embodiments are discussed or described herein. Some aspects and features of certain examples and embodiments may be implemented conventionally and these are not discussed or described in detail in the interests of brevity. It will thus be appreciated that aspects and features of apparatus and methods discussed herein which are not described in detail may be implemented in accordance with conventional techniques for implementing such aspects and features.
The present disclosure relates to an aerosol provision device configured to heat an aerosol generating material, an aerosol provision system (including an article comprising an aerosol generating medium), and a method of controlling an aerosol provision device.
In some embodiments, the aerosol provision system is an electronic cigarette, also known as a vaping device or electronic nicotine delivery system (END), although it is noted that the presence of nicotine in the aerosol generating material is not a requirement.
In embodiments, the aerosol provision device is configured for heating, but not burning or combusting, an aerosol-generating material. Thus, the aerosol provision system is in embodiments a "non-combustible" aerosol provision system (sometimes referred to as "an aerosol provision system" or a "heat-not-burn" system). In embodiments, the aerosol provision device is a tobacco heating device. The aerosol provision device could alternatively or additionally heat any other suitable and desired aerosol-generating material that is capable of generating aerosol.
In embodiments, the aerosol provision device comprises a power source (e.g. an energy storage device) and a controller. The power source may be configured to provide power to the heating element of the aerosol provision device. The controller may control the provision of power to the heating element, for example, as will be described in more detail below.
The aerosol provision device may comprise any other suitable and desired features that an aerosol provision device typically comprises, such as any one or more of: a housing, a mouthpiece, and a filter.
The aerosol-generating material is a material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way. Aerosol-generating material may, for example, be in the form of a solid, liquid or semi-solid (such as a gel) (or combinations thereof) which may or may not contain an active substance and/or flavourants.
The aerosol-generating material (which may be heated by aerosol provision device to generating aerosol) may include any plant based material, such as tobacco-containing material and may, for example, include one or more of tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes.
The aerosol-generating material alternatively or additionally may include other, non-tobacco, products, which, depending on the product, may or may not contain nicotine (and so, for example, could be substantially free from botanical material, for example being substantially tobacco free).
The aerosol-generating material may for example be in the form of a solid, a liquid, a gel, a wax or the like. The aerosol-generating material may for example also be a combination or a blend of materials. The aerosol-generating material may also be known as "smokable material".
The aerosol-generating material may comprise a binder and an aerosol former. Optionally, an active and/or filler may also be present. Optionally, a solvent, such as water, is also present and one or more other components of the aerosol-generating material may or may not be soluble in the solvent.
The aerosol-generating material may comprise or be an "amorphous solid". The amorphous solid may be a "monolithic solid". In some embodiments, the amorphous solid may be a dried gel. The amorphous solid is a solid material that may retain some fluid, such as liquid, within it. In some embodiments, the aerosol-generating material may, for example, comprise from about 50wt%, 60wt% or 70wt% of amorphous solid, to about 90wt%, 95wt% or 100wt% of amorphous solid.
The aerosol-generating material may comprise an aerosol-generating film. The aerosol-generating film may comprise or be a sheet, which may optionally be shredded to form a shredded sheet. The aerosol-generating sheet or shredded sheet may be substantially tobacco free.
In embodiments, the aerosol generating device is configured to receive a consumable article (sometimes referred to as an "article") comprising the aerosol generating material for heating. The aerosol provision device may accordingly be configured receive an article within an article receiving portion, and to power the heating element to heat an article received within an article receiving portion.
An "article" in this context is a component that includes or contains in use the aerosol generating material, which is heated to volatilise the aerosol generating material, and optionally other components in use. A user may insert the article into the aerosol generating device before it is heated to produce an aerosol, which the user subsequently inhales. The article may be, for example, of a predetermined or specific size that is configured to be placed within a heating chamber of the device which is sized to receive the article.
In embodiments, an article for use with the aerosol provision device may comprise an aerosol-generating material, and any one or more of: an aerosol-generating material storage area, an aerosol-generating material transfer component, an aerosol generator, an aerosol generation area, a housing, a wrapper, a filter, a mouthpiece, and/or an aerosol-modifying agent.
Fig. 1 shows a schematic view of an aerosol provision system 102 according to an embodiment of the present disclosure. The aerosol provision system 102 comprises an aerosol provision device 100, in accordance with an embodiment of the invention, together with an article 120 comprising an aerosol generating material.
The aerosol provision device 100 shown in Fig. 1 comprises an article receiving portion 110 which is configured to receive the article 120 when the aerosol provision device 100 is in use. The article receiving portion 110 may be in the form of a cavity or chamber within the aerosol provision device 100 for receiving the article 120 therein. It will be appreciated, however, that the article receiving portion 110 may take any suitable form that is capable of receiving the article 110.
As depicted, the article 120 may be separate to (e.g. separable or removable from) the aerosol provision device 100, and may comprise one or more electrical connectors which correspond with one or more electrical connectors of the article receiving portion 110, enabling a circuit of the aerosol provision device 100 to detect when the article 120 is inserted into the article receiving portion 110. The article 120 comprises an aerosol generating material, which when heated will produce an aerosol which can be inhaled by a user of the aerosol provision system 102. As set out above, the aerosol generating material may comprise any suitable material.
The aerosol provision device 100 includes a heating arrangement 125, which is configured to heat the article 120 when received within the article receiving portion 110. The heating arrangement comprises a heating element 130 configured to heat up when power is supplied thereto by way of a first electrical connector 131 and a second electrical connector 132 connected to a power supply 150.
In embodiments, the heating element 130 defines at least part of the article receiving portion 110. In this way, when an article 120 is inserted into the article receiving portion 110 heat is transferred from the heating element 130 to the article 120. In embodiments, the heating element 130 is configured to directly contact the article when inserted.
The heating element 130 may be hollow and adapted to receive an article 120 therein, for example as is the case for the heating element 130 shown in Fig. 2.
The hollow shape of the heating element 130 could be constant in cross sectional area along its longitudinal axis L, for example as shown in Fig. 2. Alternatively, the cross-sectional area could vary along the longitudinal axis L in either a continuous or discontinuous manner, for example tapering towards a proximal (mouth) end 135 of the heating element 130 (so that the cross-sectional area narrows as an article is inserted).
In the embodiment shown in Fig. 2, the hollow heating element 130 is tubular (cylindrical). However, the configuration of a hollow heating element 130 naturally extends to other shaped configurations. For example, the heating element 130 may be arranged as a hollow prism, such as a quadrilateral or hexagonal prism (so that the cross section of the tubular heating arrangement a polygon, such as a quadrilateral or a hexagon).
The shape of the heating element may accordingly be any suitable and desired shape for receiving an article.
The heating element could be formed of a single (continuous) piece, for example as shown in Fig. 2. The heating element could alternatively be formed of (comprise) plural pieces, which could for example be adjacent and contact one another, or could be separated relative to each another. For example, the heating element could comprise one or more hollow pieces positioned along the longitudinal direction L of the heating element, for example as shown in Fig. 3C.
Whilst various of the figures show a heating element which is hollow, into which an article can be inserted, the heating element could alternatively comprise one or more pieces which are not hollow, e.g. which are planar. For example Fig. 3D shows a heating element formed of a planar piece. Each piece could be placed along (e.g. arranged so as to define) a side of the article receiving portion 110, or multiple sides of the article receiving portion 110.
In embodiments, the heating element 130 (whether provided as a single piece, or plural pieces) may have substantially the same length as the length L1 of the article receiving portion 110, for example as shown in Fig. 1.
Whilst various possible formats for the heating element are discussed above and shown in the figures, any suitable and desired size and shape of heating element could be used, for transferring heat to an aerosol generating material (which aerosol generating material could be provided within an article, or in any other suitable and desired way). As will be appreciated, the skilled person is capable of implementing a variety of configurations for the heating element consistent with the present disclosure.
The aerosol provision device 100 may comprise a power supply (power source) 150. The heating element 130 may be connected to the power supply 150 by (at least) a first electrical connector 131 and a second electrical connector 132.
The power source 150 may comprise, for example, at least one of: a battery (which may be single use or be rechargeable), a rechargeable capacitor (e.g. a rechargeable super capacitor), a rechargeable solid-state battery (SSB), a rechargeable lithium-ion battery (LiB) or the like, a hermetically sealed battery, a pouch cell battery or some combination thereof. The power source 150 may be charged by plugging a power supply into the aerosol provision device 100, or the power source 150 may be replaceable, e.g. in the form of a replaceable battery.
The aerosol provision device 100 may also comprise a controller 160 for controlling the provision of power from the power source 150 to the heating element 130, for example as will be described in more detail below.
The heating element 130 could be connected to the power supply (power source) 150 by more than two electrical connectors (by the first electrical connector 131, the second electrical connector, and one or more further electrical connectors). In that case, in use, a pair of electrical connectors to supply power to may be selected (by the control circuit 160).
The connection between the power source 150, the electrical connectors 131, 132 and the control circuit 160 is not shown in the figures, however these components could be electrically connected in any suitable and desired way.
Various other components may be included in the aerosol provision device 100, such as an activation switch or button, and any other components common to aerosol provision devices. However, for the sake of brevity, these components are not discussed here. Notwithstanding this, the skilled person would readily appreciate, if necessary, how to utilise some or all of these components when implementing the present invention.
According to the present disclosure, the heating element comprises a semiconductor material.
The Applicant has recognised that semiconductor material can be used to generate heat resistively by causing current to flow through it (by providing power to the semiconductor material via electrical connectors), so that a semiconductor material can advantageously be used in the heating element 130 of an aerosol generating device 100 to generate heat. The heating element comprising the semiconductor material may thus be considered to form a resistive heating element.
The Applicant has furthermore recognised that barrier effects (e.g. potential energy differences) arising between the semiconductor material of the heating element and the electrical connector(s) can surprisingly contribute to heating in the vicinity of the electrical connector(s) when power is supplied, and can advantageously be used to generate additional heat adjacent the electrical connectors. The Applicant has found that formation of a Schottky barrier (as the barrier effect), between the semiconductor material of the heating element and an electrical connector formed of metal, is particularly effective for providing additional heat.
The Applicant has furthermore recognised that barrier effects (e.g. such as a Schottky barrier) between the semiconductor material of the heating element and one or more of the electrical connectors can advantageously be used to provide additional heat where it is needed most. For example, additional heat can be generated adjacent an electrical connector positioned near a proximal (mouth) end of the heating element, to reduce time to first puff of aerosol. Alternatively, or additionally, selecting (by the control circuit) which electrical connectors of a plurality of electrical connectors to supply power to, can allow additional heat generation adjacent those particular selected electrical connectors (and so provide additional heat to corresponding regions of an article, e.g. to control generation of aerosol from those regions of the article).
In embodiments, the heating element and electrical connectors are configured so as to provide a variation in the rate of heating throughout the heating element, with a greater rate of heating in regions adjacent either or both of the electrical connectors to which power is provided compared to a region between the electrical connectors.
Alternatively, or additionally, in embodiment, the heating element and electrical connectors may be configured such that, when power is supplied, (substantially the entirety of) the region between the electrical connectors is heated as a result of barrier effects where those electrical connectors contact the semiconductor material of the heating element. In embodiments, the barrier effects contribute a greater amount of heat to the region between the electrical connectors compared to resistive heating effects). This could be done, for example by positioning the electrical connectors in relatively close proximity to one another.
The Applicant has recognised that heating due to barrier effects (e.g. such as a Schottky barrier) can be tailored by configuring the electrical connectors (e.g. shape, size, material, etc.), by configuring the semiconductor (e.g. shape, size, material, amount of doping, etc.), and also by controlling the direction of current flow across the junction between the semiconductor material an electrical connector.
Example heating elements, and electrical connector configurations, and control schemes, are discussed in more detail below.
By way of example only, and to illustrate the concepts described herein, Figs. 4A and 4B are images from a thermal video recording the temperature of a tubular heating element 130 (having the shape illustrated in Fig. 2) formed of silicon carbide (SiC) semiconductor material in response to supplying power to first and second electrical connectors 131, 132 which are formed of metal and positioned at respective longitudinal ends 135, 136 of the tubular heating element.
Fig. 4A is an image showing the temperature of the heating element after 1 second of providing power to the electrical connectors. Figure 4B shows the temperature after 5 seconds of providing power. The dark circle in Fig. 4A at point Sp4 is a drop of water placed on the heating element, which has evaporated by 5 seconds and so is absent from Fig. 4B. Prior to providing power, the heating element was at room temperature.
It can be seen from Fig. 4A that, for at least an initial time duration (at least initially), the temperature in a first region "a" adjacent the first electrical connector 131 and the temperature in a second region "b" adjacent the second electrical connector 132 is greater than a temperature in a third region "c" between the first and second regions. After some time, as shown in Fig. 4B, the heating element may reach an essentially uniform temperature.
The additional heating (at least initially) in the regions "a" and "b" adjacent the electrical connectors, is due to the Schottky barrier formed between the semiconductor heating element and each of the metal electrical connectors. In comparison, in region "c" away from the electrical connectors, heating is primarily due to resistive heating arising as a result of current flow through the semiconductor.
Fig. 5 is a graph showing in more detail the change in temperature in the regions "a", "b" and "c", as a function of time as power is supplied to the heating element.
In particular, Fig. 5 shows the temperature at point Sp3 in the first region "a", at point Sp1 in the second region "b", and at point sp2 in third region "c". The temperatures for these points are derived from the thermal video.
As can be seen from Fig. 5, at least initially (in this example, for at least an initial time duration of 1 second), the rate of heating (rate of temperature increase) in the first region "a" (measured at Sp3) and the rate of heating in the second region "b" (measured at Sp1) are greater than the rate of heating in the third region "c" (measured at Sp2).
In the example shown in Fig. 5, at least initially, the rate of temperature increase in regions "a" and "b" is greater than 150 degrees Celsius per second, whereas in region "c" the rate of temperature increase is less than 150 degrees Celsius per second.
As a result of the additional heating in the first and second regions "a" and "b", at least initially (up until around 5 seconds in the example shown in Fig. 5) the temperature in the first region "a" (measured at Sp3) and the temperature in the second region "b" (measured at Sp3) are greater than the temperature in the third region "c" (measured at Sp1).
After some time (after about 1 second of supplying power in the example shown in Fig. 5), the rate of heating (rate of temperature increase) may start to equalise between the regions, which may be due to the amount of heat generated due to barrier effects changing as temperature increases. In the example shown in Fig. 5, by about 5 seconds, the heating element is substantially of a uniform temperature.
In the example shown in Figs. 4A, 4B and 5, power is provided such that the first electrical connector 131 forms a positive junction, and the second electrical connector 132 forms a negative junction, with current being caused to flow between the first and second electrical connectors accordingly.
As can be seen from Fig. 5, the rate of heating (and temperature) in the region "a" adjacent the positive electrical connector (measured at Sp3) is greater than the rate of heating (and temperature) in the region "b" adjacent the negative electrical connector (measured at Sp1). This illustrates the Applicants finding that the direction of current flow across the junction between the semiconductor material and the electrical connectors can affect the amount of additional heat created due to barrier effects (such as the Schottky barrier).
The arrangement shown and described with respect to Figs. 4A, 4B and 5 is an example of an arrangement for the heating element and electrical connectors consistent with the present disclosure. However, the present disclosure is not so limited, and various features of the heating element and electrical connectors can be modified within the scope of the present disclosure, for example as will be described in more detail below.
In embodiments, the present disclosure provides a heating arrangement for an aerosol provision device, comprising a heating element comprising semiconductor material, and first and second electrical connectors, which are configured so that when power is supplied to the electrical connectors, a rate of heating in a first region adjacent the first electrical connector and/or a rate of heating in a second region adjacent the second electrical connector is, for at least an initial time duration (at least initially), greater than a rate of heating in a third region between the first and second regions. In embodiments, the additional heating in the first and/or second regions compared to the third region is due to barrier effects (e.g. a Schottky Barrier) between the semiconductor material of the heating element and either or both of the electrical connector(s) (whereas the third region is heated is primarily due to resistive heating).
The first region adjacent the first electrical connector, the second region adjacent the second electrical connector and the third region between the first and second regions can be any suitably defined region obeying the rate of heating relationship mentioned above. The first, second, and third regions are in embodiments directly adjacent one another (for example as illustrated by regions "a", "b", and "c" of Figs. 4A and 4B).
The first, second and third regions may be defined within a continuous heating element (comprising a single, continuous, piece of material) (for example as illustrated in Figs. 4A and 4B). Each of the first, second and third regions may be a continuous region of the heating element.
In embodiments, there is no physical difference (e.g. in terms of semiconductor material used, shape, or other physical properties) between the "first", "second" and "third" regions of the heating element. In this case, the difference in rate of heating between the "first", "second", and "third" regions arise as a result of appropriately positioning the electrical connectors to which power is provided.
Alternatively, there may be a physical difference in the heating element among the first, second and third regions. For example, the heating element could differ in size (e.g. cross-sectional shape, cross-sectional area, thickness, or any other shape parameter) and/or material properties (e.g. a type of semiconductor material, an amount of dopant material, a type of dopant material, or any other material property) between any of the first, second and third regions.
Fig. 7C, for example shows a heating element 130 which differs in size (cross sectional area) between the first region "a" (adjacent the first electrical connector 131), the second region "b" (adjacent the second electrical connector 132), and the third region "c" (between the first and second regions). Fig. 7D for example shows a heating element 130 which has a greater amount of dopant material 170 in the second region "b" compared to the first region "a" and third region "c".
The temperature of the heating element is not necessarily constant in each of the first, second and third regions. For example, a continuous variation in temperature across the heating element may arise, for example as shown in Fig. 4A.
The first and second regions of the heating element are 'adjacent' the respective first and second electrical connectors, in the sense that they generally approach (e.g. extend outwards from) the first and second electrical connectors respectively.
In embodiments, when power is supplied, the rate of heating (or the temperature) of the heating element is for at least an initial time duration (at least initially) greater in the first region adjacent the first electrical connector and/or the second region adjacent the second electrical connector, compared to the third region. This relationship is maintained for a period of time commencing when power is supplied to the heating element (and throughout which power is supplied). In this regard, power may be supplied to commence a session of usage of the aerosol provision device, or power may be supplied within a session of usage of the aerosol provision device.
Immediately before power is supplied, the heating element may be at approximately room temperature (approximately 25 degrees Celsius). Alternatively, immediately before power is supplied, the heating element could be at an elevated temperature compared to room temperature (but which is less than an operating temperature for the aerosol provision device).
In embodiments, the rate of heating of the heating element is greater in the first region adjacent the first electrical connector and/or the second region adjacent the second electrical connector, compared to the third region, for at least an initial period (time duration) of 0.25 seconds, or 0.5 seconds, or 1.0 seconds during supply of power. After this time, the rate of heating in one or more of the regions may begin to equalise.
In embodiments, the rate of temperature increase in the first region and/or the second region is, for at least an initial time duration (at least initially), at least 50 degrees Celsius per second, or at least 75 degrees Celsius per second, or at least 100 degrees Celsius per second, or at least 150 degrees Celsius per second.
In embodiments, when supplying power, the temperature of the heating element is greater in the first region adjacent the first electrical connector and/or the second region adjacent the second electrical connector, compared to the third region, for an initial period of time from at least 0 seconds, or from at least 0.1 seconds, or at least 0.2 seconds, or at least 0.3 seconds during supply of power, in embodiments up to at least 2 second, or at least 3 seconds, or at least 4 seconds, or at least 5 seconds during supply of power (after supply of power commences). In embodiments, in this period of time, sufficient heat is provided from the first and/or second regions (but, in embodiment, not from the third region) to generate an aerosol.
In embodiments, when power is supplied, the first region and/or the second region reach an operating temperature for aerosol provision faster than the third region. The operating temperature for generating aerosol may be, for example, at least 150 degrees Celsius, or at least 200 degrees Celsius, or at least 250 degrees Celsius.
In the examples shown in Figs. 4A, 4B and 5, the heating element 130 is formed of a single piece of silicon carbide (SiC) semiconductor material. The Applicant has found silicon carbide to be useful for providing resistive heating and also providing heating due to barrier effects at the electrical connectors. Another semiconductor which may be useful for this purpose is gallium nitride. Other semiconductors could be used for this purpose, however, if desired.
Thus, in embodiments, the heating element comprises a semiconductor material comprising silicon carbide and/or gallium nitride.
The semiconductor material may be doped. For example, in embodiments where the semiconductor material comprises silicon carbide, it may be doped with nitrogen or phosphorous, in order to make a n-type semiconductor. Alternatively, the silicon carbide could be doped with beryllium, boron, aluminium or gallium to form a p-type semiconductor. Obtaining a p-type or an n-type semiconductor will result in a respective decrease or increase in conductivity of the doped semiconductor when heated.
As used herein, the term "heating element" may be understood as corresponding to that element which generates heat when power is supplied to it, for example to heat an article inserted into the aerosol generating device.
The heating element could be formed entirely of semiconductor material (which may or may not be doped), and is embodiments this is done. In such embodiments, heat is generated in the heating element only as a result of power being supplied to the semiconductor material via the electrical connectors.
In embodiments, the heating element (which may have any of the shapes discussed above, for example) is formed of a single piece of semiconductor material. However, it could alternatively be formed of plural pieces semiconductor material.
Consistent with embodiments of the present disclosure, the heating element may be configured such that semiconductor material of the heating element contacts at least one electrical connector formed of metal (so as to create a Schottky Barrier to generate heat when power is provided to the heating element via the electrical connector).
This could be achieved by providing a heating element formed substantially of semiconductor material. However, this could equally be achieved by using semiconductor material in combination with one or more materials which are not semiconductors in the heating element, provided at least some semiconductor material contacts an electrical connector formed of metal.
Thus, the heating element could comprise, in addition to semiconductor material, one or more other materials, for example such as one or more materials conventionally used in resistive heating elements (such as for example a metal, metal alloy, a ceramic material, or other suitable and desired material). For example, a piece of semiconductor material could be placed in contact with at least one (e.g. each) of the electrical connectors (whereas one or more other (conductive) materials are provided elsewhere in the heating element, e.g. between the semiconductor material)). In this regard, the electrical connectors could (each) interface with semiconductor material which is coupled (at least in part) with a cheaper conductive material in between.
It would be possible to form each of the electrical connectors of the same material (e.g. of a same metal), and in embodiments this is done. For example, in the example shown in Figs. 4A, 4B and 5 both electrical connectors 131 and 132 are formed of a same metal. A pair of nickel connectors, and a pair of copper connectors were used during the testing.
However, it will be understood that any suitable and desired metal could be used for one or more of (e.g. both of) the electrical connectors, such as one or more of (or combinations of): nickel, copper, molybdenum, platinum, chromium, tungsten, and aluminium. Other materials capable of forming a Schottky Diode with a semiconductor material (and which could be used one or more of (e.g. both of) the electrical connectors) include metal silicides, such as palladium silicide and platinum silicide.
In embodiments, one or more of the electrical connectors may be formed of different materials. For example, one or more of the electrical connectors could be formed of a different metal to at least one other electrical connector.
In this regard the Applicant has found that different metals create a Schottky Barrier (potential energy barrier) of a different height, and so generate a different amount of heat in the heating element when power is provided. As such, by selecting appropriate metals for the electrical connectors the amount of heat generated in the regions adjacent electrical connectors when power is supplied, can be tailored.
It would be possible to form a Schottky barrier where each electrical connector contacts the heating element (by forming each electrical connector of metal directly contacting semiconductor material of the heating element), and in embodiments this is done.
However, it is equally possible to configure the heating assembly so that a Schottky barrier is formed only at one or more of (a subset of) the electrical connectors, with no Schottky barrier being formed at the other one or more of (subset of) electrical connectors, and in embodiments this is done. For example, a Schottky barrier may be formed between the heating element and only one of the first and second electrical connectors 131, 132.
This could be done, for example, if it is desired to provide additional heat due to barrier effects adjacent only certain electrical connector(s) and not at others.
For example, and in embodiments, a first electrical connector 131 near the mouth end 135 of the heating assembly 130 may form a Schottky barrier, to provide a reduced time to first puff (whereas a second electrical connector 132 nearer the distal end 136, or indeed any other electrical connectors, may not form a Schottky barrier). In this regard, the amount of heat generated (rate of temperature increase) in a region adjacent an electrical connector which does not form a Schottky barrier will be less than the amount of heat generated (rate of temperature increase) in a region adjacent an electrical connector does form a Schottky barrier.
A Schottky barrier may be prevented, for example, and in embodiments, by forming one or more of the electrical connectors of an electrically conductive material which is not a metal (e.g. an electrically conductive ceramic, or other electrically conductive material).
Alternatively or additionally, a Schottky barrier may be prevented, in embodiments, by preventing the semiconductor material of the heating element from contacting one or more metal electrical connectors, for example by positioning a conducting material which is not metal (e.g. an electrically conductive ceramic, or other electrically conductive material) between the semiconductor material of the heating element and the electrical connector.
For those electrical connectors which do cause barrier effects (e.g. do form a Schottky barrier) at the junction between the electrical connector and the semiconductor material of the heating element, the amount of heat (the rate of temperature increase) generated in the region adjacent the electrical connector due to the barrier effects (e.g. Schottky barrier) may be tailored in various ways, for example, by appropriately selecting one or more of: the material of the electrical connector; the surface area of the electrical connector; the shape of the heating element in the region adjacent the electrical connector; the material properties of the heating element in the region adjacent the electrical connector; and the direction of current flow in the heating element (the direction of current flow across the junction between the electrical connector and the semiconductor material of the heating element).
Accordingly, in embodiments, one of more of the electrical connectors (for example a first electrical connector 131 and second electrical connector 132 to which power is provided) differ in one or more of: surface area (size and/or shape), and material. By way of example, Figs. 7A and 7C shows heating elements 130 provided with electrical connectors 131 and 132 that differ in size.
In embodiments, the shape of the heating element is not uniform, in embodiments such that the shape of the heating element differs among one or more of the regions adjacent the electrical connectors. For example, the heating element could differ in any one or more of: cross-sectional shape; cross-sectional area; thickness, or any other shape parameter. By way of example, Fig. 7C shows a heating element 130 which varies in cross-sectional area, tapering towards a mouth end 135, so that the heating element has a cross-sectional smaller area in the region adjacent the first electrode 131 compared to the region adjacent the second electrode 132.
In embodiments, one or more material properties of heating element are not uniform, in embodiments differing among one or more of the regions adjacent the electrical connectors. For example, there could be difference in one or more of: a type of semiconductor material; an amount of dopant material; a type of dopant material; or any other material property of the heating element. By way of example, Fig. 7D shows a heating 130 arrangement in which the amount of dopant material 170 varies within the heating element, the heating element being doped more heavily towards one of the electrical connectors 132 compared to another electrical connector 131.
Thus, in embodiments, a shape and/or material property of the heating element varies (differs) among one or more of the regions adjacent the electrical connectors (for example differing in a first region adjacent a first electrical connector compared to a second region adjacent a second electrical connector to which power is provided).
In embodiments, a shape and/or material property of the heating element varies (differs) in one or more of the region adjacent the electrical connectors compared to regions between those electrical connectors (for example differing in a first region adjacent a first electrical connector and/or a second region adjacent a second electrical connector, compared to a third region between the first and second regions). The shape and/or material property of the heating element which differ may be any of those described above.
As discussed above with reference to Figs. 4A, 4B and 5, the direction of current flow across the junction between the semiconductor and the electrical connector can also affect the rate of heating in the region adjacent the electrical connector. Thus, in embodiments, rate of heating in a first region adjacent a first electrical connector differs from a rate of heating in a second region adjacent a second electrical connector, in embodiments at least in part due a difference in the direction of current flow across the junction between the semiconductor material of the heating element and the electrical connector.
Thus, (as will be apparent from the above discussion), in embodiments, the rate heating in the regions adjacent respective electrical connectors may differ (for example with a rate of heating in a first region adjacent a first electrical connector, differing from the rate of heating in the second region adjacent the second electrical connector). The rate of heating may differ for at least an initial time duration (at least initially) when power is provided to the electrical connectors. The rate of heating may begin to equalise over time. This is illustrated, for example, in Fig. 5.
In embodiments, when applying power to a first and second electrical connector of the heating assembly, the rate of heating (rate of temperature increase) in a first region adjacent a first electrical connector differs from the rate of heating in a second region adjacent a second electrical connector, for a period (for an initial time duration) of at least 0.1 seconds, or least 0.2 seconds, or at least 0.3 seconds during which power is supplied, in embodiments up to at least 2 seconds, or at least 3 seconds, or at least 4 seconds, or at least 5 seconds.
Whilst the above discussion has referred to first and second electrical connectors, more than two electrical connectors could be provided (so that the heating arrangement also comprises one or more further electrical connectors). The above discussion equally applies to any additional electrical connectors (so that barrier effects, e.g. Schottky barrier, may arise in the region adjacent any electrical connector, and for example by tailored as discussed above).
By providing more than two electrical connectors, it is possible to selectively heat different regions of the heating element, by selecting which electrical connectors to provided power to (so as to cause heating due to barrier effects in the region adjacent either or both of the electrical connectors to which power is provided).
By way of example, Fig. 3B shows a heating element 130 with more than two electrical connectors 131, 132, 133. Such a heating element could be formed by positioning the electrical connectors on a surface of a heating element formed of a single (undivided) piece of material, or could be formed by positioning electrical connectors between adjacent pieces of material of the heating element.
Fig. 3C shows another example of a heating element a heating element 130 with more than two electrical connectors. In this example, the heating element is divided into plural pieces 133', each having a respective pair of electrical connectors 131 and 132, and 131' and 132'.
In embodiments where more than two electrical connectors are provided, any pair of the electrical connectors can be referred to as a notional 'first' electrical connector, and 'second' electrical connector to which power may be applied, and may have any of the features discussed above.
For example, with reference to Fig. 3B, during a session of usage power could be applied to 'first' electrical connector 131, and 'second' electrical connector 132, with electrical connector 133 not being provided with power. Alternatively, power could be applied to electrical connector 132 as the 'first' electrical connector, and to electrical connector 133 as the 'second' electrical connector with electrical connector 131 not being provided with power, or any other suitable and desired permutations in which a pair of the electrical connectors forming a 'first' and 'second' electrical connector are provided with power.
In embodiments, the first and second electrical connectors (to which power can be provided) are configured so that the first electrical connector 131 is closer towards the mouth end 135 of the heating element (closer towards a mouth end of the aerosol provision device) than the second electrical connector 132. This may allow a greater rate of heating to be provided in the first region adjacent the first electrical connector (near the mouth end of the heating element (aerosol provision device)), for example compared to a rate of heating in the second region adjacent the second first electrical connector and/or compared to a rate of heating in the third region between the first and second regions. This may allow a relatively fast time to first puff of aerosol.
In embodiments where more than two electrical connectors are provided, then in embodiments the electrical connectors are spaced along the longitudinal axis L of the heating element 130. An example such configuration is shown in Fig. 3B. However, it will be appreciated that electrical connectors could be provided at any suitable and desired position, for example wherever it is desired to provide additional heating due to barrier effects.
It is noted that although Figs. 3A to C and Figs. 7A to D show a pair of electrical connectors positioned at the distal ends 135, 136 of the heating element 130, electrical connectors could be placed at any other suitable and desired locations of the heating element. For example, electrical connectors could instead be positioned near (for example, inwards of) the distal ends of the heating element.
It is also noted that whilst Figs. 3A to C and Figs. 7A to D show electrical connectors which cover an end of, or encircle, the heating element, this is not necessary and any other suitable and desired shape of electrical connector could be used. By way of example, Fig. 7B illustrates first and second electrical connectors 131, 132 which do not encircle the heating element.
As discussed above, the heating element and electrical connectors may be configured such that, when power is supplied, a rate of heating in a first region adjacent a first electrical connector and/or a rate of heating in a second region adjacent a second electrical connector is, for at least an initial time duration (at least initially), greater than a rate of heating in the third region. In this regard, the electrical connectors may be spaced far enough apart that there is a variation it the rate of heating at different locations of the heater, with regions adjacent either or both the electrical connectors being additionally heated due to barrier effects (e.g. Schottky barrier), a region away from the electrical connectors is not heated by barrier effects and so has a lesser rate of heating. As discussed above, this variation in heating may advantageously be used to selectively heat certain regions of the heating element.
It would also be possible to provide one or more electrical connectors which are sufficiently close together so that the rate of heating substantially does not vary between the electrical connectors (in other words, so that barrier effects (e.g. Schottky barrier) cause heating throughout the entire region between the electrical connectors). The various features discussed above still equally apply in such embodiments (for example, the heating due to barrier effects may be tailored in any of the ways discussed above).
In such embodiments, one or more electrical connectors (for example, forming a first electrical connector and a second electrical connector to which power is supplied) are separated by a distance of at most 2 cm, or at most 1 cm, or at most 0.5 cm.
This could be done, for example, by providing a first electrical connector 131 on an interior surface of a hollow heating element, and a second electrical connector 132 on an exterior surface of the hollow heating element. The first and second electrical connectors could cover the entire interior surface and the entire exterior surface respectively of the heating element, for example as shown in Fig. 8B. Alternatively, first and second electrical connectors could cover only part of the entire interior surface and exterior surface of the heating element.
This could additionally or alternatively be done by providing first and second electrical connectors 131, 132 which are positioned in close proximity along the longitudinal axis L of the heating element 130, for example as shown in Fig. 8A. These could be provided in combination with one or more additional electrical connectors 133 which are spaced further apart (and for which the rate of heating varies in the region between those electrical connectors compared to in the region(s) adjacent those electrical connectors).
As discussed above, the aerosol provision device may be controlled by a controller 160. The controller may be configured to select which 'first' and 'second' electrical connectors to provide power to (so as to generate heat due to barrier effects at either of both of the selected electrical connectors). The controller may also be configured to control the direction of current flow to affect the amount of heat generated due to barrier effects (and so control a rate of heating in a first region adjacent a first electrical connector and/or a second region adjacent a second electrical connector).
Figure 9 is a flowchart showing example control steps when operating a heating element in accordance with embodiments of the present disclosure. In embodiments, when it is desired to heat a region of the heating element (step 90), which pair of 'first' and 'second' electrical connectors are to be provided with power is selected, and optionally a direction for current flow is selected, and power is provided accordingly (step 91). If it is subsequently desired to heat a different region of the heating element (step 92), then it is determined whether a different pair of electrical connectors should be provided with power and/or whether current should be caused to flow in a different direction, and power is provided accordingly (step 93).
Thus, in embodiments, when controlling an aerosol provision device in accordance with the present disclosure, current may be caused to flow in a first direction in the heating element, and then subsequently be caused to flow in a different (opposite) direction. This may be done, for example, to initially create a greater rate of heating in a first region adjacent a first electrical connector compared to a second region adjacent a second electrical connector, and to then change the direction of current flow (without changing the electrical connectors which power is provided to) to create a greater at in the second region than the first region.
For example, (e.g. within a session of usage), which electrical connectors power is provided to and/or the current flow may initially be selected to provide a greater rate of heating at a mouth end of the heating element compared to a distal end of the heating element (and then be changed to create a greater rate of heating at the distal end of the heating element compared to the mouth end of the heating element). This may assist with providing a faster time to first puff.
This is illustrated in Figs. 6A, in which current is initially provided in a direction which causes a greater rate of heating at the mouth end 135 of the heating element than at the distal end 136 (for example with an electrical connector at the mouth end forming a positive junction, and an electrical connector at the distal end forming a negative junction). As illustrated in Fig. 6B, the current of current flow may then be reversed to cause a greater rate of heating at the distal end 136 of the heating element compared to the mouth end 135 of the heating element.
Alternatively, it may be the case that, when selecting a different pair of electrical connectors to provide power to, a region which is desired to be heated adjacent an electrical connector may provide a better (e.g. greater) rate of heating if the current is provided in a particular direction which may be opposite to the direction of current flow previously.
Which electrical connectors power is provided to and/or the current flow could be changed within a session of usage (whilst an article remains inserted), to alter the rate of heating in different regions of the heating element (and any article therein). In such embodiments, the electrical connectors which power is provided to and/or the direction current flow could remain constant for an initial, e.g. selected, e.g. predetermined, period of time, before they are (permitted to be) changed.
Alternatively or additionally the electrical connectors which power is provided to and/or the direction of current flow could be changed between sessions of usage (when a different article is inserted), for example to tailor aerosol generation to desired user experience of each usage sessions and/or to tailor the heating to differently configured articles.
The various embodiments described herein are presented only to assist in understanding and teaching the claimed features. These embodiments are provided as a representative sample of embodiments only, and are not exhaustive and/or exclusive. It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects described herein are not to be considered limitations on the scope of the invention as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the claimed invention. Various embodiments of the invention may suitably comprise, consist of, or consist essentially of, appropriate combinations of the disclosed elements, components, features, parts, steps, means, etc., other than those specifically described herein. In addition, this disclosure may include other inventions not presently claimed, but which may be claimed in future.

Claims

An aerosol provision device comprising a heating arrangement configured to heat an aerosol generating material, comprising:
a heating element comprising a semiconductor material;

wherein the heating element is electrically connected to a power supply by a first electrical connector and a second electrical connector;

wherein the heating element comprises a first region adjacent the first electrical connector, a second region adjacent the second electrical connector, and a third region between the first and second regions, wherein when power is supplied a rate of heating in the first region and/or a rate of heating in the second region is, for at least an initial time duration, greater than a rate of heating in the third region.
The aerosol provision device of claim 1, wherein when power is supplied, the rate of heating in the first region and/or the second region comprises, at least initially, a rate of temperature increase of at least 50 degrees Celsius per second.
The aerosol provision device of any preceding claim, wherein when power is supplied, the rate of heating in the first region adjacent the first electrical connector, at least initially, differs from the rate of heating in the second region adjacent the second electrical connector.
The aerosol provision device of any preceding claim, wherein the first electrical connector is formed of a different material than the second electrical connector, and/or wherein the first electrical connector contacts the heating element with a different surface area compared to the second electrical connector.
The aerosol provision device of any preceding claim wherein the first electrical connector and/or the second electrical connector comprises a metal and forms a Schottky Barrier with the semiconductor material of the heating element.
The aerosol provision device of any preceding claim, wherein the semiconductor material comprises at least one of: silicon carbide or gallium nitride.
The aerosol provision device of any preceding claim, comprising an article receiving portion for receiving, in use, an article comprising an aerosol generating material, wherein the heating element is configured to heat an article received within the article receiving portion.
The aerosol provision device of any preceding claim, wherein the aerosol provision device has a mouth end and a distal end; and
wherein the first electrical connector contacts the heating element closer towards the mouth end of the aerosol provision device than the second electrical connector.
The aerosol provision device of claim 8, wherein when power is supplied, current is caused to flow between the first and second electrical connectors in a direction which causes a greater rate of heating in the first region adjacent the first electrical connector than the second region adjacent the second electrical connector.
The aerosol provision device of any preceding claim, comprising a controller configured to control the direction of current flow through the heating element when power is supplied to the heating element, to control a rate of heating in the first region and/or the second region of the heating element.
An aerosol provision system comprising:
the aerosol provision device of any preceding claim; and

an article comprising an aerosol generating medium.
A method of controlling a heating arrangement of an aerosol provision device,
the heating arrangement comprising a heating element comprising a semiconductor material, and a power supply electrically connected to the heating element by a two or more electrical connectors, the method comprising:
providing power to the heating element via a first electrical connector and a second electrical connector of the electrical connectors, to cause a first region of the heating element adjacent the first electrical connector and/or a second region of the heating element adjacent to the second electrical connector to heat, for at least an initial time duration, at a greater rate of heating than a third region between the first and second regions.
The method of claim 12 comprising controlling the direction of current flow through the heating element when power is supplied to the heating element, to control a rate of heating in the first region and/or the second region of the heating element.
The method of claim 12 or 13, wherein the first electrical connector contacts the heating element closer towards a mouth end of the aerosol provision device than the second electrical connector, and wherein current is caused to flow between the first and second electrical connectors in a direction which causes a greater rate of heating in the first region adjacent the first electrical connector than the second region adjacent the second electrical connector.
The method of any one of claims 12 to 14 comprising subsequently providing power to a different pair of electrical connectors.