RU2506668C1 - Melted electrolyte for chemical current source - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention refers to electrical engineering, in particular, to development of melted electrolytes based on lithium and potassium salts for chemical current sources. Melted electrolyte for chemical current source that includes lithium metavanadate and potassium salts is distinguished by the fact that among potassium salts it contains bromide and metavanadate with the following ratio of components, by wt %: lithium metavanadate 33.26-35.20, potassium bromide 4.79-7.72, potassium metavanadate 57.08-61.11.

EFFECT: reduction of temperature and specific enthalpy for melting of the above electrolyte allows increasing scope of its use within the range of temperatures 329-347° C, thus reducing power expenditures for preparing electrolyte to operating condition.

1 ex, 1 tbl

Description

The invention relates to the field of the electrical industry, in particular to the development of molten electrolytes for chemical current sources based on lithium and potassium salts.

Known electrolyte for chemical current sources, including bromide and lithium metavanadate. It is characterized by a relatively high melting point of 473 ° C and a specific melting enthalpy of 172 kJ / kg (Garkushin I.K., Gubanova T.V., Frolov E.I. Phase equilibria in systems involving lithium salts. - Yekaterinburg: Ural Branch of RAS, 2010 .-- 121 p.).

Known electrolyte, including lithium and potassium metavanadates and potassium chloride. It has a melting point of 410 ° C and a specific melting enthalpy of 188 kJ / kg (Garkushin I.K., Gubanova T.V., Petrov A.S., Anipchenko B.V. Phase equilibria in systems involving metavanadates of certain alkali metals. - M.: Mechanical Engineering-1, 2005. - 118 p.).

Known electrolyte for chemical current sources, including lithium metavanadate and lithium and potassium chlorides with a melting point of 347 ° C and a specific melting enthalpy of 180 kJ / kg (Garkushin I.K., Gubanova T.V., Petrov A.S., Anipchenko B .V. Phase equilibria in systems with the participation of metavanadates of certain alkali metals. - M.: Mashinostroenie-1, 2005. - 118 p.).

However, this electrolyte has high values of temperature and specific enthalpy of melting, which reduces the range of its use in temperature and further increases the energy consumption for putting it into working condition.

The novelty of the claimed composition compared to the known ones is that the electrolyte contains lithium and potassium metavanadates and potassium bromide.

The technical result is to reduce the melting temperature and specific enthalpy of melting of the salt composition. The technical result is achieved by fused ingredients in certain proportions, which are obtained by studying a three-component mixture of salts of potassium bromide, lithium metavanadates and potassium.

The proposed electrolyte is prepared as follows. The initial pre-dehydrated salts are weighed, placed in a platinum microtigger in a shaft-type heating furnace and melted. The ratio of ingredients and melting temperature of the compositions for the claimed limits are as follows:

Example 1

0.0998 g (33.26 wt.%) Lithium metavanadate +0.0201 g (6.71 wt.%) Potassium bromide +0.1801 g (60.03 wt.%) Potassium metavanadate.

The melting point is 33 ° C.

The specific enthalpy of melting is 157 kJ / kg

Example 2

0.1023 g (34.10 wt.%) Lithium metavanadate + 0.0144 g (4.79 wt.%) Potassium bromide +0.1833 g (61.11 wt.%) Potassium metavanadate.

The melting point is 333 ° C.

The specific melting enthalpy is 158 kJ / kg

Example 3

0.1024 g (34.15 wt.%) Lithium metavanadate + 0.0173 g (5.76 wt.%) Potassium bromide + 0.1803 g (60.09 wt.%) Potassium metavanadate.

The melting point is 331 ° C.

The specific enthalpy of melting is 156 kJ / kg

Example 4

0.0956 g (35.20 wt.%) Lithium metavanadate + 0.02 10 g (7.72 wt.%) Potassium bromide +0.1550 g (57.08 wt.%) Potassium metavanadate.

The melting point is 332 ° C.

The specific enthalpy of melting is 157 kJ / kg

Beyond the stated limits, the composition is not single-phase and has a higher melting point.

The table shows the comparative characteristics of the claimed composition and composition selected as a prototype.

Compositions The composition of the mixture, wt.% Specific enthalpy of melting, kJ / kg Melting point, ° С one* 2 3 Prototype, LiCl-LiVO ₃ -KCl 39.75 6.38 53.87 180 347 Offered, LiVO ₃ -KBr-KVO ₃ one 33.26 6.71 60.03 157 331 2 34.10 4.79 61.11 158 333 3 34.15 5.76 60.09 156 331 four 35,20 7.72 57.08 157 329 * indicates the serial number of salt in the system.

The inventive electrolyte has a significant advantage over the known ones - the melting temperature is reduced by 14-18 ° C and the specific melting enthalpy is reduced by 22-24 kJ / kg, which reduces the energy consumption for bringing the electrolyte into working condition and extends the temperature range of using the electrolyte.

Claims (1)

A molten electrolyte for a chemical current source, including lithium metavanadate and potassium salts, characterized in that bromide and metavanadate are taken as potassium salts in the following ratio of components, wt.%:
lithium metavanadate 33.26 ... 35.20 potassium bromide 4.79 ... 7.72 potassium metavanadate 57.08 ... 61.11