RU2530893C2 - Electrolyte for chemical current source (versions) - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention is related to electrical engineering industry, in particular to development of melting electrolyte for chemical current sources that includes lithium metavanadate and lithium and potassium salts, at that among lithium salts the electrolyte contains fluoride and bromide and among potassium salts it contains potassium bromide with the following mass ratio of the components (wt %): lithium fluoride 2.18-2.52, lithium bromide 50.86-52.83, lithium metavanadate 3.60-4.81, potassium bromide 41.38-43.35. The invention is also referred to melting electrolyte for a chemical current source that includes lithium metavanadate and lithium and potassium salts, at that among lithium salts the electrolyte contains chloride, bromide and metavanadate with the following mass ratio of the components (wt %): lithium metavanadate 42.59-44.40, potassium chloride 2.15-2.79, potassium bromide 2.42-2.99, potassium metavanadate 50.30-52.73.

EFFECT: reduction of melting temperature for the salt compound.

2 cl, 1 tbl, 10 ex

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 potassium chloride and lithium metavanadate. It is characterized by a relatively high melting point of 426 ° C (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 s).

Known electrolyte, including metavanadates of lithium and potassium, and lithium fluoride, with a melting point of 405 ° C. The disadvantage is the high melting point (Garkushin I.K., Gubanova T.V., Petrov A.S., Anipchenko B.V. Phase equilibria in systems involving metavanadates of certain alkali metals. - M.: Mashinostroenie-1, 2005. - 118 s).

Known electrolyte for chemical current sources, including lithium bromide and metavanadate and potassium bromide with a melting point of 330 ° C (Zolotukhina E.V., Gubanova T.V., Garkushin I.K. Three-component reciprocal system Li, K || Br, VO _{.. 3} // International Conference on chemical XT'12 technology T. 1 .: Abstracts -... M., 2012. - S.82-83). This electrolyte is taken as a prototype.

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

The novelty of the claimed compositions in comparison with the known lies in the fact that the proposed electrolytes contain lithium fluoride and bromide and potassium metavanadate.

The technical result is to reduce the melting temperature and specific enthalpy of melting of salt compositions.

The technical result for option 1 is achieved by fusion of lithium metavanadate and lithium salts of potassium in the following ratio of components (wt.%):

Lithium fluoride 2.18 ... 2.52 Lithium bromide 50.86 ... 52.83 Lithium metavanadate 3.60 ... 4.81 Potassium bromide 41.38 ... 43.35

The technical result for option 2 is achieved by fusion of lithium metavanadate and potassium salts in the following ratio of components (wt.%):

Lithium metavanadate 42.59 ... 44.40 Potassium chloride 2.15 ... 2.79 Potassium bromide 2.42 ... 2.99 Potassium metavanadate 50.30 ... 52.73

The proposed electrolytes are prepared as follows. The initial pre-dehydrated salts are weighed, placed in a platinum microtigger in a shaft-type heating furnace and melted.

For 1 variant of the electrolyte, the ratio of ingredients and the melting temperature of the compositions of the claimed limits are as follows:

Example 1

0.0080 g (2.52 wt.%) Lithium fluoride + 0.1637 g (51.67 wt.%) Lithium bromide + 0.0110 g (3.67 wt.%) Lithium metavanadate + 0.1337 g ( 42.14 wt.%) Potassium bromide.

The melting point is 322 ° C.

Example 2

0.0065 g (2.19 wt.%) Lithium fluoride + 0.1570 g (52.83 wt.%) Lithium bromide + 0.1229 g (3.60 wt.%) Lithium metavanadate + 0.0107 g ( 41.38 wt.%) Potassium bromide.

The melting point is 324 ° C.

Example 3

0.0061 g (2.18 wt.%) Lithium fluoride + 0.1432 g (50.86 wt.%) Lithium bromide + 0.0102 g (3.61 wt.%) Lithium metavanadate + 0.1221 g (43.35 wt.%) Potassium bromide.

The melting point is 323 ° C.

Example 4

0.0063 g (2.2 wt.%) Lithium fluoride + 0.1467 g (51.22 wt.%) Lithium bromide + 0.0138 g (4.81 wt.%)) Lithium metavanadate + 0.1196 g (41.77 wt.%) potassium bromide. The melting point is 321 ° C.

Example 5

0.0055 g (2.23 wt.%) Lithium fluoride + 0.1281 g (51.82 wt.%) Lithium bromide + 0.0091 g (3.68 wt.%) Lithium metavanadate + 0.1045 g ( 42.27 wt.%) Potassium bromide.

The melting point is 320 ° C.

The ratio of ingredients and melting temperature of the compositions for the claimed limits of the 2 options for the electrolyte are as follows:

Example 1

0.1332 g (44.40 wt.%) Lithium metavanadate + 0.0064 g (2.15 wt.%) Potassium chloride + 0.0084 g (2.81 wt.%) Potassium bromide + 0.1519 g ( 50.64 wt.%) Potassium metavanadate.

The melting point is 318 ° C.

Example 2

0.1299 g (43.29 wt.%) Lithium metavanadate + 0.0076 g (2.63 wt.%) Potassium chloride + 0.0079 g (2.53 wt.%) Potassium bromide + 0.1546 g ( 51.55 wt.%) Potassium metavanadate.

The melting point is 320 ° C.

Example 3

0.1297 g (43.24 wt.%) Lithium metavanadate + 0.0069 g (2.29 wt.%) Potassium chloride + 0.0090 g (2.99 wt.%) Potassium bromide + 0.1544 g ( 51.48 wt.%) Potassium metavanadate.

The melting point is 321 ° C.

Example 4

0.1278 g (42.59 wt.%) Lithium metavanadate + 0.0068 g (2.26 wt.%) Potassium chloride + 0.0073 g (2.42 wt.%) Potassium bromide + 0.1582 g ( 52.73 wt.%) Potassium metavanadate.

The melting point is 319 ° C.

Example 5

0.1323 g (44.12 wt.%) Lithium metavanadate + 0.0084 g (2.79 wt.%) Potassium chloride + 0.0084 g (2.79 wt.%) Potassium bromide + 0.1510 g ( 50.30 wt.%) Potassium metavanadate.

The melting point is 313 ° C.

Beyond the stated limits, the compositions are not single-phase and have 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.% Melting point, ° C one* 2 3 four Prototype, LiBr-LiVO ₃ -KBr 50.40 3.34 46.26 - 330 Offered, LiF-LiBr-LiVO ₃ -KBr one 2,52 51.67 3.67 42.14 322 2 2.19 52.83 3.60 41.38 324 3 2.18 50.86 3.61 43.35 323 four 2.2 51.22 4.81 41.77 321 5 2.23 51.82 3.68 42.27 320

Offered, LiVO ₃ -KCl-KBr-KVO ₃ one 44.40 2.15 2.81 50.64 318 2 43.29 2.63 2,53 51.55 320 3 43.24 2.29 2.99 51.48 321 four 42.59 2.26 2.42 52.73 319 5 44.12 2.79 2.79 50.30 313

* indicates the serial number of salt in the system.

The inventive electrolytes have a significant advantage over the known ones - the melting temperature is reduced by 10-17 ° C, which extends the range of use of the compositions in temperature.

Claims (2)

1. A molten electrolyte for a chemical current source, including lithium metavanadate and lithium, potassium salts, characterized in that it contains fluoride and bromide as lithium salts, and its bromide as potassium salt in the following ratio of components (wt.%):
Lithium fluoride 2.18 ... 2.52 Lithium bromide 50.86 ... 52.83 Lithium metavanadate 3.60 ... 4.81 Potassium bromide 41.38 ... 43.35 2. A molten electrolyte for a chemical current source, including lithium metavanadate and lithium, potassium salts, characterized in that its potassium salts contain its chloride, bromide and metavanadate in the following ratio of components (wt.%):
Lithium metavanadate 42.59 ... 44.40 Potassium chloride 2.15 ... 2.79 Potassium bromide 2.42 ... 2.99 Potassium metavanadate 50.30 ... 52.73