WO2025012233A1

WO2025012233A1 - Aerosol generation device heat shielding

Info

Publication number: WO2025012233A1
Application number: PCT/EP2024/069253
Authority: WO
Inventors: Tilen CEGLAR; Jaakko MCEVOY; Grzegorz Aleksander PILATOWICZ
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2023-07-10
Filing date: 2024-07-08
Publication date: 2025-01-16
Anticipated expiration: 2026-01-10

Abstract

There is provided an aerosol generation device (100, 200) configured to generate an aerosol from an aerosol generating substrate (326). The aerosol generation device comprises a heating chamber (102) configured to receive and heat the aerosol generating substrate. A phase change material (116) is configured to absorb heat energy. The phase change material is axially displaced from the heating chamber. A heat transfer layer (118) is configured to transfer heat flowing outwardly from the heating chamber through the aerosol generation device to the phase change material.

Description

AEROSOL GENERATION DEVICE HEAT SHIELDING

FIELD OF THE INVENTION

The present invention relates to aerosol generation devices, and more specifically to heat shielding for aerosol generation devices.

BACKGROUND

Aerosol generation devices such as electronic cigarettes and other aerosol inhalers or vaporisation devices are becoming increasingly popular consumer products.

Heating devices for vaporisation or aerosolisation are known in the art. Such devices typically include a heating chamber and heater. In operation, an operator inserts the product to be aerosolised or vaporised into the heating chamber. The product is then heated with an electronic heater to vaporise the constituents of the product for the operator to inhale. In some examples, the product is a tobacco product similar to a traditional cigarette. Such devices are sometimes referred to as “heat not bum” devices in that the product is heated to the point of aerosolisation, without being combusted.

Problems faced by known aerosol generation devices include providing effective heat shielding.

SUMMARY OF INVENTION

In an aspect, there is provided an aerosol generation device configured to generate an aerosol from an aerosol generating substrate, the aerosol generation device comprising: a heating chamber configured to receive and heat the aerosol generating substrate; a phase change material configured to absorb heat energy, wherein the phase change material is axially displaced from the heating chamber within the aerosol generation device; and a heat transfer layer configured to transfer heat flowing outwardly from the heating chamber through the aerosol generation device to the phase change material. Aerosol generation devices deliver relatively high thermal energy to the consumable or substrate in order to generate sufficient aerosol to satisfy the consumer. The heat source can excessively heat other components in the device, which need to be protected. Typically this is achieved by using thermal insulation with a very low thermal conductivity to thermally manage the system. However, sufficiently insulating the device in this way can lead to the device having an excessively large form factor that is not preferable to the consumer.

To conform with the requirement for a small form factor for the aerosol generation device, heat needs to be appropriately managed. The present invention reduces the dimensions of the aerosol generation device by laterally spreading heat that leaks from the heat source, and guiding it to a phase change material acting as a heat sink that is axially displaced from the heating chamber. In this way, excessive temperatures on the outer surfaces, or at other components in the device, are prevented and the waste or leaked heat energy is released into these other components over longer periods of time thereby inhibiting heat damage. Moreover, through the use of the phase change material, less thermal insulation is needed, and the axial displacement of the phase change material from the heating chamber means that the phase change material does not contribute to the thickness of the device. An aerosol generation device with a smaller form factor and adequate heat shielding is therefore provided.

Preferably, the heat transfer layer at least partially surrounds the heating chamber.

In this way, the leaked heat from the heating chamber is effectively and efficiently transferred to the phase change material.

Preferably, the aerosol generation device further comprises a thermal insulation layer at least partially surrounding the heating chamber and configured inhibit a flow of heat outwardly from the heating chamber.

In this way, the flow of leaked heat to the outer surfaces of the aerosol generation device is mitigated, thereby improving the consumer comfort. Also, the thermal insulation concentrates the heat flow into the heating chamber, to the substrate, thereby improving energy efficiency.

Preferably, the heat transfer layer is embedded in the thermal insulation layer.

In this way, a practical implementation is provided that avoids transferring too much heat energy from the heating chamber to the phase change material. This arrangement improves the maintaining of heat in the heating chamber, to adequately heat the substrate, whilst avoiding excess heat reaching the outer casing or surface of the device.

In an alternative aspect, there is provided an aerosol generation device configured to generate an aerosol from an aerosol generating substrate, the aerosol generation device comprising: a heating chamber configured to receive and heat the aerosol generating substrate; a phase change material configured to absorb heat energy, wherein the phase change material is axially displaced from the heating chamber within the aerosol generation device; a heat transfer layer configured to transfer heat flowing outwardly from the heating chamber through the aerosol generation device to the phase change material; and electronics comprising a controller that controls a heating operation of the aerosol generating device, wherein the phase change material is positioned between the electronics and the heating chamber.

Preferably, the aerosol generation device further comprises a heater, and the electronics further comprise a battery and the heater is powered by the battery.

Preferably, the aerosol generation device further comprises at least one supercapacitor module at least partially surrounding the heating chamber.

The supercapacitor module is advantageous because the higher discharge rate from a supercapacitor allows for a faster pre-heating than using a battery. This is particularly advantageous for ceramic flat heaters which have high power requirements. By positioning the supercapacitor module adjacent to the heating chamber rather than separated from it, the size of the aerosol generation device can be reduced by making a better use of physical space, thereby providing a compact aerosol generation device. This can be easier for the operator to hold and use, as well as store and transport. The user experience is therefore improved. The heat transfer layer shields the supercapacitor module from leaked heat from the heating chamber by channelling this thermal energy to the phase change material, away from the supercapacitor module.

Preferably, the at least one supercapacitor module is separated from the heating chamber by the thermal insulation layer.

In this way, the supercapacitor module is further shielded from thermal energy leaked from the heating chamber, thereby improving the supercapacitor module operation.

Preferably, the phase change material is arranged to not overlap the heating chamber in a radial direction in the aerosol generation device.

In this way, the phase change material is completely axially separated from the heating chamber, leading to a smaller device thickness.

Preferably, the heat transfer layer comprises graphite.

Graphite has a strong anisotropic thermal conductivity which improves the heat flow to the phase change material rather than the outer surfaces of the aerosol generation device. This improves the heat management.

Preferably, a contact area between the heat transfer layer and the phase change material is in the range of 10 to 100 mm².

This range of contact areas has been found to be particularly beneficial in transferring heat from the heat transfer layer to the phase change material. This improves the heat management.

Preferably, a contact area between the heat transfer layer and the phase change material is approximately 50 mm². This contact area has been found to be particularly beneficial in transferring heat from the heat transfer layer to the phase change material. This improves the heat management.

Preferably, the heat transfer layer has an anisotropic thermal conductivity such that in-plane thermal conductivity in a direction toward the phase change material is higher than out-of-plane thermal conductivity perpendicular to the direction toward the phase change material.

In this way, heat management is improved by the heat transfer layer directing the heat energy to the phase change material rather than the outer surface of the aerosol generation device.

Preferably, the in-plane thermal conductivity in the direction toward the phase change material is in the range of 1000-2000 W/(mK).

This range of in-plane thermal conductivity has been found to be particularly beneficial in transferring heat to the phase change material. This improves the heat management.

Preferably, the out-of-plane thermal conductivity perpendicular to the direction toward the phase change material is less than 30 W/(mK).

This range of in-plane thermal conductivity has been found to be particularly beneficial in inhibiting heat transfer to the outer surface of the aerosol generation device. This improves the heat management.

Preferably, the heating chamber is cylindrical and configured to receive a rodshaped aerosol generating substrate.

Preferably, the heating chamber is a flat cuboid shape, and configured to receive a planar aerosol generating substrate. BRIEF DESCRIPTION OF DRAWINGS

Embodiments of the invention are now described, by way of example, with reference to the drawings, in which:

Figure 1 is a conceptual cross-sectional diagram of a first aerosol generation device;

Figure 2 is a conceptual cross-sectional diagram of a second aerosol generation device; and

Figure 3 is a conceptual heat transfer map for the aerosol generation device of Figure 2.

DETAILED DESCRIPTION

Figure 1 is a conceptual cross-sectional diagram of a first aerosol generation device 100, also known as a vapor generation device or an electronic cigarette. The cross-section is viewed perpendicular to the axial direction 108 of the aerosol generation device 100; that is, a cut-away view along the length of the aerosol generation device 100, in the radial direction 110.

For the purposes of the present application, it will be understood that the terms vapor and aerosol are interchangeable. The aerosol generation device 100 is configured to heat an aerosol generating material without burning the aerosol generating material, to generate an aerosol. The aerosol generating material can comprise tobacco, or a combination of tobacco with other constituents such as one or more humectants. Alternatively, or additionally, the aerosol generating material can comprise other non-tobacco materials suitable for generating an aerosol, such as aerosol generating liquids.

The aerosol generation device 100 has a heating chamber 102 into which an aerosol generating substrate is received. The aerosol generating substrate can comprise, or can itself be, an aerosol generating material. The aerosol generation device 100 can have an opening 103 through which the aerosol generating substrate is inserted into the heating chamber 102. A heater in the heating chamber 102 is configured to heat the aerosol generating substrate, without burning it, to produce an aerosol that can be inhaled by a consumer. In some examples, the electronics 106 include a battery and the heater is powered by the battery.

In an example, the aerosol generating substrate can contain an aerosol generating material, such as a tobacco rod containing tobacco. A tobacco rod can be similar to a traditional cigarette. The heating chamber 102 can have a cross-section approximately equal to that of the aerosol generating substrate. The heating chamber 102 can have a circular or substantially circular cross-sectional shape to match that of the tobacco rod aerosol generating substrate.

The heating chamber 102 can have a depth such that when the associated aerosol generating substrate is inserted into the heating chamber 102, a first end portion of the aerosol generating substrate reaches a bottom of the heating chamber 102 (that is, an end of the chamber 102 distal from the opening 103), and a second end portion of the aerosol generating substrate distal to the first end portion extends outwardly from the heating chamber 102 through the opening 103. In this way, a consumer can inhale upon the aerosol generating substrate when it is inserted into the aerosol generation device 100.

The heater can be arranged in the heating chamber 102 such that the aerosol generating substrate engages the heater when inserted into the heating chamber 102. In an example, the heater can be arranged as a tube defining the heating chamber 102 such that when the first end portion of the aerosol generating substrate is inserted into the heating chamber 102 the heater substantially or completely surrounds the portion of the aerosol generating substrate within the heating chamber 102. The heater can be a wire, such as a coiled wire heater, a thin film heater wrapped around a heating chamber, or a ceramic heater with a heating track optionally embedded into the ceramic or located outside or around the ceramic, or any other suitable type of heater. The heater can be embedded into the walls of the heating chamber 102 or attached to the inner or outer surface of the heating chamber walls. In an alternative, the heater can be arranged as an elongate piercing member (such as in the form of needle, rod or blade) within the heating chamber 102; in such an example the heater can be arranged to penetrate the aerosol generating substrate and engage the aerosol generating material when the aerosol generating substrate is inserted into the cavity. In another alternative, the heater may be in the form of an induction heater. In such an embodiment, a heating element (i.e., a susceptor) can be provided in the aerosol generating substrate, and the heating element is inductively coupled to the induction element (i.e., induction coil) in the heating chamber 102 when the aerosol generating substrate is inserted into the heating chamber 102. The induction heater then heats the heating element by induction.

The heater is arranged to heat the tobacco (or other aerosol generating material), without burning the tobacco, to generate an aerosol. That is, the heater heats the tobacco at a predetermined temperature below the combustion point of the tobacco such that a tobacco-based aerosol is generated. The skilled person will readily understand that the aerosol generating substrate does not necessarily need to comprise tobacco, and that any other suitable substance for aerosolisation (or vaporisation), particularly by heating without burning the substance, can be used in place of tobacco or in combination with the tobacco.

Alternatively, to the rod-like (i.e., traditional cigarette type) aerosol generating substrate, the aerosol generating substrate can be planar or flat in shape, for example in the form of flat-shaped cuboid. The heating chamber 102 can be dimensioned to match the shape of the substrate as a flat shape. That is, the heating chamber 102 can have substantially the same cross-sectional shape as the aerosol generating substrate. The substrate can be considered planar in shape in that it has a depth that is much shorter than the length and width. In such examples, the substrate can be a planar cartridge that is received in the heating chamber 102; an optional mouthpiece (not shown) can then be placed over the opening 103 for the consumer to inhale upon in an aerosolisation session.

In an example of an aerosol generation device configured to receive such a planar aerosol generating substrate, the heating chamber 102 can be cup-shaped with the opening 103 forming the open end of the cup, and an opposing end which in some cases can include air inlets or can be sealed. Walls of the heating chamber 102 can comprise one or more heating elements of a heater (not shown in Figure 1 ) therein or thereon. Each, or one or more of, the walls of the heating chamber 102 can have a heating element therein or thereon. Walls of the heating chamber 102 can be ceramic with heater wires or tracks embedded therein or thereon. In an example, the heating elements can be arranged in contact with one of the heating chamber walls outside of the heating chamber 102. In another example, the heating element(s) can be embedded within the chamber walls. In another example, the heating element(s) can be on the chamber walls, internal to the heating chamber 102. As explained, the chamber walls can be a ceramic material with a heater track or wire therein or thereon. In an alternative, each heating element may comprise a polyimide film heater extending along substantially the total area of the outer surface of the corresponding heating wall or only along a part of this surface.

In an example of an aerosol generation device configured to receive such a planar aerosol generating substrate, the heating chamber 102 can have two major internal faces corresponding the opposing wider faces of the planar aerosol generating substrate, and two minor internal faces corresponding to the opposing narrower faces of the planar aerosol generating substrate. The minor internal faces can be perpendicular to the major internal faces, and connect the major internal faces. The walls of the heating chamber 102 corresponding to the major internal faces can be arranged with heater wires or tracks embedded therein or thereon forming two ceramic heaters. In some examples, walls of the heating chamber 102 corresponding to the minor internal faces can also be ceramic. Such ceramic heaters can provide a compact heating chamber 102 with well-distributed heat directed to the planar aerosol generating substrate. However, such ceramic heaters can require considerably more power to heat than the heater of an aerosol generation device that is configured to receive a more traditional cigarette or cigarette-like consumable. This increased power requirement can be due to the larger volume and specific heat compared to thin wall heaters (e.g., stainless steel cups). Such heaters therefore greatly benefit from heating power management utilising one or more supercapacitors, as will be described in herein.

In other examples of an aerosol generation device configured to receive such a planar aerosol generating substrate, each of the walls can be of a thermally conductive material, such as a metal, notably a stainless steel. Additionally, at least some of the walls or all of these walls can form one single piece.

The internal dimensions of the heating chamber 102 can be defined so that an airflow channel is formed between the walls of the heating chamber 102 and the aerosol generating substrate when inserted therein. Alternatively, the airflow may come from air inlets arranged at or toward the rear of the chamber, rather than passing by the substrate.

Whilst planar and cylindrical heating chambers and substrates have been discussed, in other examples, the aerosol generating substrate and corresponding heating chamber 102 can be of other suitable shapes or dimensions.

The heating chamber 102 is arranged at a first end portion 112 of the aerosol generation device 100. The electronics 106 of the aerosol generation device 100 can be arranged a second end portion 114 of the aerosol generation device 100. The first end portion 112 and the second end portion 114 are distal to one another along an axial direction 108 of the aerosol generation device 100. The axial direction 108 can be considered a ‘lengthways’ direction along the longer length of the aerosol generation device 100, and the radial direction 110 can be considered a ‘widthways’ direction (perpendicular to the axial direction 108) along the shorter length of the aerosol generation device 100. In the example of Figure 1 , the axial direction 108 is the direction of insertion of the aerosol generating substrate into the aerosol generation device 100.

The electronics 106 can comprise a controller that controls the operation of the aerosol generation device 100. This can include controlling the heater to be preheated to a temperature for aerosolising the aerosol generating material, and maintaining the heater at such an aerosolisation temperature, in an aerosolisation session. The electronics 106 can also comprise a power source used to power the heater. The power source can include one or more batteries, one or more supercapacitors, or a combination thereof.

Arranging the electronics 106 distally from the heating chamber 102 reduces the risk of damage to the electronics 106 from heat flowing outwardly from the heating chamber 102.

A thermal insulation layer 104 can surround the heating chamber 102. The purpose of the thermal insulation layer 104 is to provide heat shielding by inhibiting the spread of heat through the aerosol generation device 100. This is beneficial in improving energy efficiency by concentrating heat transfer toward the substrate (rather than through the device), improving the comfort of the consumer holding the device by inhibiting heat flow to the outer casing 107 of the aerosol generation device 100 which could be uncomfortable on the consumer’s hands, and reducing the risk of heat damage to other components in the aerosol generation device 100 (e.g., the electronics 106).

The thermal insulation layer 104 can at least partially (and preferably fully) surround the heating chamber 102 along axial length of the heating chamber 102. The thermal insulation layer 104 can also be adjacent to end of heating chamber 102 opposite opening 103. The thermal insulation layer 104 can fully encase all of heating chamber 102 other than the opening 103.

The heat shielding can be improved with the provision of a phase change material 116 and a heat transfer layer 118.

The phase change material 116 (or phase change material module) absorbs heat from the heating chamber 102 during an aerosolisation session, and changes phase from a solid to liquid phase though melting. The temperature of the phase change material plateaus during the melting as it continues to absorb heat energy. The phase change material 116 acts as a heat storage component or heat sink, whereby at the phase transition temperature, the latent heat capacity absorbs the thermal energy from the heat source. As such, the thermal heat is transformed into latent heat. This absorption of heat from the heating chamber 102 protects the electronics 106 and inhibits the heating of the casing 107 of the aerosol generation device 100, thereby also protecting the consumer holding the device. The absorbed heat is then released from the phase change material 116 after the aerosolisation session, when the device is no longer in use. Upon cooling down, the phase transition of the phase change material 116 releases the thermal energy back into the system. Thereby, the phase change material 116 mitigates excessive temperatures that can occur with high heat flux through the system, for example during the initial heating of the heater. The phase change material 116 can be a bulk phase change material.

Surrounding the heating chamber 102 with the phase change material would allow the phase change material to readily absorb the heat energy flowing through the device. However, such an arrangement causes an increased size of the aerosol generation device in the radial direction 110. This increased size can make it uncomfortable for the consumer to hold the device.

To overcome this issue, the phase change material 116 is axially displaced from the heating chamber 102 within the aerosol generation device 100. In other words, the phase change material 116 is arranged to not overlap the heating chamber 102 in the radial direction 110 in the aerosol generation device 100. In the example of Figure 1 , the phase change material 116 is positioned between the heating chamber 102 and the electronics 106. That is, the phase change material 116 is arranged between the first end portion 112 of the aerosol generation device 100 and the second end portion 114 of the aerosol generation device 100.

This allows for the aerosol generation device 100 to be smaller in the radial direction 110. However, this presents a challenge in effectively transferring the heat energy flowing from the heating chamber 102 through the device 100 to the phase change material 116 rather than to the casing 107 of the aerosol generation device 100, or other components. To address this issue, one or more heat transfer layers 118 (or heat transfer modules) are used. The heat transfer layer(s) 118 (or heat spreader) is configured to transfer heat flowing outwardly from the heating chamber 102 through the aerosol generation device 100 to the phase change material 116.

The heat transfer layer 118 can be arranged adjacent to and alongside the heating chamber 102 so that heat flowing out of the heating chamber 102 meets the heat transfer layer 118 before reaching the casing 107 of the aerosol generation device 100. The heat transfer layer 118 can at least partially (or preferably fully) surround the heating chamber 102 to maximise the transfer of leaked heat from the heating chamber 102 to the phase change material 116. The heat transfer layer 118 can be in the form of a sheet. The heat transfer layer 118 extends axially along the aerosol generation device 100 to reach the phase change material 116, where it interfaces with the phase change material 116.

Preferably, the contact area where the heat transfer layer 118 interfaces with the phase change material 116 is maximised. This ensures that as much heat as possible is transferred to the phase change material 116 from the heat transfer layer 118.

Preferably, the contact area between the heat transfer layer 118 and the phase change material 116 is in the range of 10 to 100 mm². Preferably, the contact area between the heat transfer layer 118 and the phase change material 116 is approximately 50 mm². The heat transfer can be bonded to the phase change material 116 to ensure a good contact for sufficient heat transfer therebetween.

In the example of Figure 1 , the heat transfer layer 118 is embedded in the thermal insulation layer 104. This can be brought about, for example, by the thermal insulation comprising two layers of thermal insulation, with the heat transfer layer 118 embedded between these two layers of thermal insulation 104.

In another examples, rather than being embedded in the thermal insulation layer 104, the heat transfer layer 118 can be between thermal insulation layer 104 and heating chamber 102. In another example, rather than being embedded in the thermal insulation layer 104, the heat transfer layer 118 can be outside the thermal insulation layer 104, between the thermal insulation layer 104 and the casing 107 of the aerosol generation device 100. In a further example, there may be no thermal insulation layer 104; this could be possible for a case in which the heat transfer layer 118 can effectively transfer enough leaked heat energy from the heating chamber 102, to the phase change material 116, that the thermal insulation layer 104 is not needed.

The heat transfer layer 118 can have an anisotropic thermal conductivity such that in-plane thermal conductivity in a direction toward the phase change material 116 is higher than out-of-plane thermal conductivity perpendicular to the direction toward the phase change material 116. This is advantageous as it allows for the leaked heat energy from the heating chamber 102 to be preferably directed to the phase change material 116 rather than outwardly to the casing 107 of the aerosol generation device 100. The higher the in-plane thermal conductivity, the better. Preferably, the in-plane thermal conductivity in the direction toward the phase change material 116 is in the range of 1000-2000 W/(mK). Preferably, the out-of- plane thermal conductivity perpendicular to the direction toward the phase change material 116 is less than 30 W/(mK).

An example of a suitable material for the heat transfer layer 118 is graphite. Such a graphite sheet can have, for example, an in-plane thermal conductivity of 1300 W/(mK) and an out-of-plane thermal conductivity of 18 W/(mK). In some examples, the graphite sheet can have a thickness in the range of 40 to 200 pm.

The phase change material 116 preferably has a thermal conductivity in the range of 0.2-2 W/(mK). Preferably, the thermal conductivity of the phase change material 116 is an order of magnitude higher than that of the thermal insulation layer 104. The phase change material 116 preferably has a specific heat capacity in the range of 1-3 kJ/(kgK). The phase change material 116 preferably has a latent heat capacity in the range of 100-300 kJ/kg. The phase change material 116 preferably has a phase change temperature in the range of 30-70°C.

An example of a suitable material for the phase change material 116 is a hydrated salt phase change material, which can have a thermal conductivity of approximately 0.51 W/(mK), a specific heat capacity of approximately 2 kJ/(kgK), latent heat capacity of approximately 200 kJ/kg, and a phase change temperature in the range of 30-50°C.

The thermal insulation layer 104 preferably has a thermal conductivity in the range of 0.005-0.1 W/(mK) at 20°C. An example of a suitable material for the thermal insulation layer 104 is an aerogel such as Finesulight with a thermal conductivity of approximately 0.02 W/(mK).

Figure 2 is a conceptual cross-sectional diagram of a second aerosol generation device 200 having thermal insulation layer(s) 104, heat transfer layer(s) 118, phase change material 116, electronics 106 (optionally including a battery/batteries) and casing 107 in common with the corresponding features of the first aerosol generation device 100 of Figure 1. The description of these common features is not repeated for brevity.

The aerosol generation device 200 of Figure 2 has the heating chamber 102 that is configured to receive the planar or flat aerosol generating substrate as described with reference to Figure 1. Figure 2 shows the two flat heaters 220 forming the major walls of the heating chamber 102, with the heating chamber 102 defined between these two flat heaters 220. The thermal insulation layer 104 is arranged on the opposing side of each flat heater 220 to the side of each flat heater 220 that faces internally to the heating chamber 102. The heat transfer layer 118 can be embedded in the thermal insulation layer 104 or sandwiched between two thermal insulation layers 104. The aerosol generation device 200 of Figure 2 also includes a mouthpiece 224 as described with reference to (but now shown in) Figure 1.

The aerosol generation device 200 of Figure 2 includes at least one supercapacitor module 222 separated from the heating chamber 102 by the thermal insulation layer 104. That is to say, at least one supercapacitor 222 at least partially surrounds the heating chamber 102. The supercapacitor module(s) 222 can comprise one or more supercapacitors. In some examples, there are two supercapacitor modules 222. Each of these supercapacitor modules 222 overlaps a major face of the flat heating chamber 102 and is separated from the heating chamber 102 by the thermal insulation layer 104 and the heat transfer layer 118. That is, in a radial direction 110 outward from the centre of the heating chamber 102, the following layers can be arranged: the flat heater 220 defining a major face of the heating chamber 102, a thermal insulation layer 104, a heat transfer layer 118, another thermal insulation layer 104 (or the heat transfer layer 118 is embedded in a single insulation layer 104), a supercapacitor module 222, and the casing 107 of the aerosol generation device 200.

The supercapacitor module 222 is advantageous because the higher discharge rate from a supercapacitor allows for a faster pre-heating than using a battery. This is particularly advantageous for ceramic flat heaters which have high power requirements. By positioning the supercapacitor module 222 adjacent to the heating chamber 102 rather than separated from it, the size of the aerosol generation device 200 can be reduced by making a better use of physical space, thereby providing a compact aerosol generation device 200. This can be easier for the operator to hold and use, as well as store and transport. The user experience is therefore improved. The heat transfer layer 118 shields the supercapacitor module 222 from leaked heat from the heating chamber 102 by channelling this thermal energy to the phase change material 116, away from the supercapacitor module 222.

Whilst the description of Figure 2 has been applied to a flat heater 220 forming the planar heating chamber 102 for receiving a planar substrate therein, the same principle of at least partially surrounding the heating chamber 102 with a supercapacitor module(s) 222 could be applied to cylindrical heating chamber 102 used for tobacco rod, or any other suitable type of heating chamber.

Also, whilst the description of Figure 2 has been applied to two supercapacitor modules 222 at least partially surrounding the heating chamber 102 by overlapping the major faces of the heating chamber 102, instead one or more supercapacitors 222 could be conformed or bent to surround or at least partially surround the heating chamber 102.

Figure 3 shows a conceptual heat transfer map for the aerosol generation device 200 of Figure 2.

In terms of heating a substrate 326, for the aerosolisation session, heat flows from the heater into the heating chamber 102. This heat heats a substrate 326 within the heating chamber 102. An airflow 328 is drawn into the heating chamber 102. This airflow 328 interacts with the heated substrate 326 and a heated aerosol 330 flows out for inhalation by the consumer.

In terms of leaked heat that travels through the aerosol generation device 200, away from the heating chamber 102, rather than into the heating chamber 102, some heat (i.e. , leaked heat) flows from the heater into the thermal insulation layer 104. The majority of this heat is then channelled by the heat transfer layer 118 to the phase change material 116 where is absorbed and stored. Some residual heat may continue travelling outward and reach the supercapacitor module 222, but this is greatly reduced due to the heat transfer layer 118 channelling the leaked heat to the phase change material 116.

It will be readily understood to the skilled person that the preceding embodiments in the foregoing description are not limiting; features of each embodiment may be incorporated into the other embodiments as appropriate.

Claims

1 . An aerosol generation device configured to generate an aerosol from an aerosol generating substrate, the aerosol generation device comprising: a heating chamber configured to receive and heat the aerosol generating substrate; a phase change material configured to absorb heat energy, wherein the phase change material is axially displaced from the heating chamber within the aerosol generation device; a heat transfer layer configured to transfer heat flowing outwardly from the heating chamber through the aerosol generation device to the phase change material; and electronics comprising a controller that controls a heating operation of the aerosol generating device, wherein the phase change material is positioned between the electronics and the heating chamber.

2. The aerosol generation device of claim 1 , wherein the heat transfer layer at least partially surrounds the heating chamber.

3. The aerosol generation device of any preceding claim, wherein the aerosol generation device further comprises a thermal insulation layer at least partially surrounding the heating chamber and configured inhibit a flow of heat outwardly from the heating chamber.

4. The aerosol generation device of claim 3, wherein the heat transfer layer is embedded in the thermal insulation layer.

5. The aerosol generation device of any preceding claim, wherein the aerosol generation device further comprises at least one supercapacitor module at least partially surrounding the heating chamber.

6. The aerosol generation device of claim 5 when dependent on claim 3 or claim 4, wherein the at least one supercapacitor module is separated from the heating chamber by the thermal insulation layer.

7. The aerosol generation device of any preceding claim, wherein the phase change material is arranged to not overlap the heating chamber in a radial direction in the aerosol generation device.

8. The aerosol generation device of any preceding claim, wherein the heat transfer layer comprises graphite.

9. The aerosol generation device of any preceding claim, wherein a contact area between the heat transfer layer and the phase change material is in the range of 10 to 100 mm².

10. The aerosol generation device of any preceding claim, wherein a contact area between the heat transfer layer and the phase change material is approximately 50 mm².

11 . The aerosol generation device of any preceding claim, wherein the heat transfer layer has an anisotropic thermal conductivity such that in-plane thermal conductivity in a direction toward the phase change material is higher than out-of- plane thermal conductivity perpendicular to the direction toward the phase change material.

12. The aerosol generation device of claim 11 , wherein the in-plane thermal conductivity in the direction toward the phase change material is in the range of 1000-2000 W/(mK).

13. The aerosol generation device of claim 11 or claim 1213, wherein the out- of-plane thermal conductivity perpendicular to the direction toward the phase change material is less than 30 W/(mK).

14. The aerosol generation device of any preceding claim, wherein the heating chamber is cylindrical and configured to receive a rod-shaped aerosol generating substrate.

15. The aerosol generation device of any one of claims 1 to 14, wherein the heating chamber is a flat cuboid shape, and configured to receive a planar aerosol generating substrate.

16. The aerosol generation device of any preceding claim, further comprising a heater, wherein the electronics further comprise a battery and the heater is powered by the battery.