RU2840173C2 - Ampoule with electrolyte for primary lithium current source of ampoule type manufacturing method - Google Patents

Abstract

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and can be used in production of primary lithium current sources of ampoule type. Method involves preparation of an electrolyte based on lithium tetrachloroaluminate (LiAlCl₄) in an ampoule, ampoule preparation for sealing, ampoule sealing. In order to prepare a fused salt based on lithium tetrachloroaluminate (LiAlCl₄) equimolecular amounts of initial lithium chloride (LiCl) and aluminium chloride salts are fused in a sealed ampoule (AlCl₃) at weight ratio LiCl:AlCl₃ = 42:134. Further, to prepare the electrolyte from the fused salt, an ampoule with the required amount of salt is selected, broken and the required amount of fused salt is weighed and the weighed portion is placed in a flask, the fused salt is dissolved LiAlCl₄ thionyl chloride salt. After pro check quality of prepared electrolyte and sealed in glass ampoules with capacity of up to 1000 cm³.

EFFECT: providing a safe method of making an ampoule with an electrolyte for making primary lithium current sources of an ampoule type.

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Description

The invention relates to the electrical engineering industry and can be used in the production of ampoule-type primary lithium current sources.

Sealing of ampoules generally depends on the filling method:

- when filling with a syringe, seal by pulling back the capillary;

- when filling under vacuum, they are sealed by melting the capillary.

A method for sealing vessels and a device for its implementation are known (Patent of the Russian Federation 2111926, published on 27.05.1998), which includes heating along the ring of a rotating vessel, pulling and tearing off the part of the vessel to be sealed, in which, before pulling, the part of the vessel to be sealed is shifted relative to the axis of the vessel.

Also known is a method for sealing liquid-filled ampoules (patent SU1678778, published 23.09.91), which includes rotation of the ampoule, exposure of a burner flame to a local section of the capillary, followed by pulling, in which the pulling is carried out by rotating the ampoule around an axis perpendicular to the axis of its symmetry, followed by removal of the capillary.

The closest to the claimed method is the Method of sealing glass ampoules (patent SU944575, published 23.07.82), which consists of heating the ampoule capillary for its melting, in which, to speed up the process, the ampoule capillary is inserted into a high-frequency current inductor, irrigated with liquid for washing it, and heating is carried out for 1.5 - 2 s by putting a heater on the ampoule capillary, made in the form of a steel sleeve with gaps relative to the ampoule capillary and the inductor.

The objective of the present invention is to develop a cost-effective and safe method for producing an ampoule with an electrolyte, which will subsequently be used for producing ampoule-type primary lithium current sources.

The stated problem is solved by the fact that in the claimed method of manufacturing an ampoule with electrolyte for a primary lithium current source of the ampoule type, which consists in preparation of electrolyte in an ampoule, preparation of the ampoule for sealing, sealing of the ampoule, according to the declared technical solution that to prepare an electrolyte based on lithium tetrachloroaluminate (LiAlCl4), equimolecular amounts of the initial salts of lithium chloride (LiCl) and aluminum chloride (AlCl) are fused₃) in the ratio: LiCl:AlCl₃= 42:134 (mass %), prepare a mixture of salts, weigh an ampoule for fusing salts with a stopper in a box, fill the ampoule with aluminum chloride to 2/3 of its volume, weigh the ampoule with aluminum chloride, determine the mass of aluminum chloride, calculate the required amount of lithium chloride using the ratio specified above, weigh the required amount of lithium chloride in a weighing bottle and transfer the lithium chloride sample into the ampoule with aluminum chloride through a funnel; to prepare the ampoule for sealing, close the neck of the ampoule with fluoroplastic tape, then with a stopper, transfer the ampoule from the box to a fume hood, wipe with a calico or gauze napkin to remove traces of salt, place the ampoule vertically in a glass on a layer of fabric and transfer the ampoule for sealing; to seal the ampoule, remove the fluoroplastic tape and stopper from the neck of the ampoule and seal the ampoule using a gas burner; to fuse, place the sealed ampoule in a fuser or porcelain cup, place the cup or cup with the ampoule in a drying oven and set the temperature to (175 ± 5) °C, when the main amount of aluminum chloride melts, periodically stir the contents of the ampoule by shaking and turning until the salts are completely melted, finish fusing when a transparent, homogeneous melt is obtained; to prepare an electrolyte from the fused salt, prepare a sample of the fused salt LiAlCl₄, calculate the sample size of the salt LiAlCl₄taking into account the volume of electrolyte and the molecular weight of LiAlCl₄, equal to 175.74 g, the electrolyte concentration should be (61.5 ± 8.8) g/l [(0.35 ± 0.05) mol/l], select an ampoule with the required amount of salt, dissolve the fused LiAlCl salt₄, for this purpose, dry air is supplied to the salt dissolution box located in the fume hood and a flask with salt is transferred to the box, thionyl chloride is poured into the flask with salt to half the volume of the flask and the dissolution is carried out by shaking the contents of the flask manually, thionyl chloride is added up to the mark, the flask is closed with a stopper, the flask is left in the box until the solution has completely cooled; the quality of the prepared electrolyte is checked, if necessary, after checking the quality of the electrolyte, seal it in glass ampoules with a capacity of up to 1000 cm³.

The method for producing an ampoule with electrolyte for a primary lithium current source of the ampoule type is implemented as follows:

At the first stage, lithium tetrachloroaluminate (LiAlCl4) is prepared. For this purpose, equimolecular amounts of the initial salts of lithium chloride (LiCl) and aluminum chloride (AlCl ₃ ) are fused in the ratio: LiCl:AlCl ₃ = 42:134 (mass %). A mixture of salts is prepared in advance, an ampoule for fusion of salts with a stopper is weighed in a box, the ampoule is filled with aluminum chloride to 2/3 of its volume, the ampoule with aluminum chloride is weighed, the mass of aluminum chloride is determined, the required amount of lithium chloride is calculated according to the ratio specified above, the required amount of lithium chloride is weighed in a weighing bottle and the lithium chloride sample is transferred into the ampoule with aluminum chloride through a funnel.

Then the ampoule is prepared for sealing. To do this, close the neck of the ampoule with fluoroplastic tape, then with a stopper, transfer the ampoule from the box to the fume hood, wipe it with a napkin made of calico or gauze to remove traces of salt, place the ampoule vertically in a glass on a layer of fabric and transfer the ampoule for sealing.

To seal the ampoule, remove the fluoroplastic tape and the stopper from the neck of the ampoule and seal the ampoule using a gas burner. The sealing shape is arbitrary.

After sealing, the salt mixture is fused in the sealed ampoule. To perform fusion, place the sealed ampoule in a fusion device or in a porcelain cup, install the device or cup with the ampoule in a drying cabinet and set the temperature to (175 ± 10) °C, when the main amount of aluminum chloride passes into the melt, periodically mix the contents of the ampoule by shaking and turning until the salts are completely melted. Fusion is completed when a transparent homogeneous melt is obtained. The minimum fusion time is 2-4 hours. Upon completion of the fusion process, turn off the drying cabinet, cool it to the workshop temperature and remove the ampoule from the drying cabinet.

A label indicating the date of manufacture and the mass of LiAlCl4 salt is attached to the ampoule and the ampoule is placed in a technological container, interleaved with packaging material (fabric, cotton wool). The shelf life of the fused salt is 15 years. Before use, visually check the integrity of the ampoules and the condition of the label.

The preparation of electrolyte using fused salt is carried out as follows.

Prepare a weighed portion of fused LiAlCl ₄ salt, calculate the weighed portion of LiAlCl ₄ salt taking into account the volume of electrolyte and the molecular weight of LiAlCl ₄ , equal to 176 grams. The concentration of the electrolyte should be (60 ± 10) g/l [(0.35 ± 0.05) mol/l]. Select an ampoule with the required amount of salt, place the ampoule with the salt in the weighing box, break the ampoule at the blunt end with a pestle, remove the fragments, place them in a glass, and transfer the salt to a mortar for grinding by crushing.

Weigh the required amount of salt in a weighing bottle or cup. Place the salt sample through a funnel into a measuring flask and close the flask with a stopper. Pour the remaining salt into a weighing bottle and store in a desiccator in a salt weighing box for no more than 6 months.

The fused salt LiAlCl ₄ is dissolved by feeding dry air into the salt dissolution box located in the fume hood and transferring the flask with the salt into the box. Thionyl chloride is poured into the flask with the salt to half the volume of the flask and the solution is dissolved by shaking the contents of the flask manually. Thionyl chloride is added up to the mark, the flask is closed with a stopper, and the flask is left in the box until the solution has completely cooled.

It is permissible to prepare the electrolyte without preliminary fusion of LiAlCl ₄ by dissolving the initial mixture of AlCl ₃ and LiCl salts in thionyl chloride in the ratio specified above. Dissolution is carried out by shaking the contents of the flask manually;

The resulting electrolyte is poured into a bottle, tightly closed with a lid and kept in a box for 3 days.

The presence of a fine white sediment at the bottom of the jar is allowed.

The quality of the prepared electrolyte is checked, a label is attached to the bottle indicating the batch number, date of manufacture and analysis, concentration of the electrolyte signed by the performer and the representative of the quality control department. Store the electrolyte in a box in a bottle with a tightly closed lid. The shelf life of the electrolyte is 1 year. Upon expiration of the shelf life, determine the concentration of the electrolyte before use. It is permissible to extend the shelf life of the electrolyte by 1 year after each analysis if positive results are obtained.

If necessary, after checking the quality, seal the electrolyte in glass ampoules with a capacity of up to 1000 cm ³ . Place the ampoules in a container, layer with packaging material (fabric, cotton wool), store away from heating devices. The shelf life of the electrolyte in a sealed ampoule is 10 years.

To fill the ampoules you need to:

1. Prepare the device: put a fluoroplastic tube on the needle, blow it with dried air and install it on the syringe;

2. Wipe the outer surface of the vessel with gauze soaked in alcohol and place it in the stand;

3. Wipe the end of the fluoroplastic tube thoroughly with a cloth. Fill the vessel with electrolyte to a volume of (2±0.5) ^cm3 using the device;

4. Wipe the outer and inner surfaces of the ampoule neck thoroughly with a cotton swab soaked in alcohol, then dry (to remove traces of electrolyte). Immediately transfer the ampoule for sealing. Storage of unsealed ampoules with electrolyte is not allowed.

To carry out sealing it is necessary:

1. Place the ampoule in the sealing device and put an asbestos ring on the neck of the ampoule;

2. Heat the neck of the ampoule in a burner flame;

3. Seal the neck of the ampoule, maintaining a size of 5 max;

4. Remove the asbestos ring from the neck of the ampoule. Remove the ampoule from the device, place it in the stand with the tip up and cool it in the workshop conditions;

5. Place unsealed ampoules in a desiccator with soda, close with a lid. Dispose of.

To carry out the cleaning you need:

1. Place the ampoules in a cup in one layer, fill with distilled water and close the lid;

2. Keep for 2-8 hours, using tweezers to remove ampoules that are not hermetically sealed in appearance into a desiccator with soda for disposal. It is permissible to check the ampoules using a microscope or magnifying glass, after wiping the ampoule with a cloth;

3. Carefully drain the water from the cup and refill the ampoules with distilled water;

4. Repeat steps 1, 2, 3 until the release of salt from the tip of the ampoule has completely stopped;

5. Remove the ampoules with tweezers and wipe first with dry gauze, then with gauze soaked in alcohol, especially carefully in the neck area;

6. Place the washed ampoules in the stand with the neck up. Place the unsealed ampoules in a desiccator with soda, close the lid and transfer for disposal.

To implement control it is necessary:

1. Conduct a complete inspection of the appearance of the ampoules, size 5 max neck;

2. Check the tightness of the ampoules using the thermal indicator method;

3. Carefully wipe the ampoules with gauze soaked in alcohol, especially in the neck area;

4. Place indicator paper into the sockets of the stand;

5. Place the ampoules neck down into the sockets of the stand;

6. Place the ampoules in a heating cabinet with a temperature of (55±10) °C and keep at this temperature for (20±10) minutes;

7. After the holding time has elapsed, remove the ampoules from the cabinet;

8. Visually determine the change in color of the indicator paper, which indicates that the ampoule is not hermetically sealed;

9. Remove any unsealed ampoules from the stand socket and send them for disposal;

10. Keep the sealed ampoules in workshop conditions for 10 days;

11. Repeat steps 4 through 7;

12. If there are any leaky ampoules, repeat the leak test. The frequency of testing is (4±1) days. If two times zero waste is obtained, the batch is considered suitable.

Claims (1)

A method for manufacturing an ampoule with an electrolyte for a primary lithium current source of the ampoule type, including the preparation of an electrolyte based on lithium tetrachloroaluminate (LiAlCl ₄ ) in an ampoule, preparing the ampoule for sealing, sealing the ampoule, characterized in that for the preparation of a fused salt based on lithium tetrachloroaluminate (LiAlCl ₄ ), equimolecular quantities of the initial salts of lithium chloride (LiCl) and aluminum chloride (AlCl ₃ ) are fused at a mass ratio of LiCl:AlCl ₃ = 42:134, wherein for the preparation of a mixture of the initial salts, an ampoule for fusion of salts with a stopper is weighed in a weighing bottle, the ampoule is filled with aluminum chloride to 2/3 of its volume, the ampoule with aluminum chloride is weighed, the mass of aluminum chloride is determined, the required amount of chloride is calculated lithium according to the ratio specified above, weigh the required amount of lithium chloride in a weighing bottle and transfer the lithium chloride sample into an ampoule with aluminum chloride through a funnel, while to prepare the ampoule for sealing, close the neck of the ampoule with fluoroplastic tape, then with a stopper, transfer the ampoule from the weighing bottle to a fume hood, wipe with a calico or gauze napkin to remove traces of salt, place the ampoule vertically in a glass on a layer of fabric and transfer the ampoule for sealing, and to seal the ampoule, remove the fluoroplastic tape and stopper from the neck of the ampoule and seal the ampoule using a gas burner, while to fuse, place the sealed ampoule in a porcelain glass, place the porcelain glass with the ampoule in a drying cabinet and set the temperature to 175±5°C, when the main amount passes aluminum chloride into the melt, periodically stir the contents of the ampoule by shaking and turning until the salts are completely melted, finish melting when a transparent homogeneous melt is obtained, to prepare an electrolyte from the fused salt, prepare a weighed portion of the fused salt LiAlCl ₄ , while calculating the amount of the weighed portion of the LiAlCl ₄ salt taking into account the volume of the electrolyte and the molecular weight of LiAlCl ₄ , equal to 175.74, select an ampoule with the required amount of salt, break it and weigh the required amount of salt of the fused salt and place the weighed portion in a flask, dissolve the fused salt LiAlCl ₄ , for this purpose, feed it into a box for dissolving salts, located in a fume hood, with dried air and transfer a flask with a weighed portion of the fused salt to the box, pour thionyl chloride into the flask with the fused salt to half the volume of the flask and dissolve by shaking the contents of the flask manually, add thionyl chloride up to the mark, close the flask with a stopper, leave the flask in the box until the solution has completely cooled, check the quality of the prepared electrolyte, then seal it in glass ampoules with a capacity of up to 1000 cm ³ .