RU2316853C1 - Method for manufacturing sealed nickel-cadmium battery - Google Patents

Abstract

FIELD: electrical engineering; sealed nickel-cadmium batteries using cloth-separator.

SUBSTANCE: proposed method for manufacturing sealed nickel-cadmium batteries includes assembling stack of plates with separating material placed between positive and negative plates, placing this assembly into battery case, pouring electrolyte, conducting charge-discharge cycles, and replacing electrolyte. This is followed by cycling in aqueous solution of potassium hydroxide of 240-320g/l concentration and in aqueous solution of potassium hydroxide of 300-350 g/l concentration adding 15-35 g/l of lithium hydroxide in charge-discharge-charge sequence; by end of charge under current electrolyte is drained and cycling is conducted in aqueous solution of potassium hydroxide using electrolyte of 100-110 g/l concentration in discharge-charge-discharge sequence; by end of discharge electrolyte is drained. In the process plates are kept in electrolyte for 10-15 minutes prior to cycling in lithium hydroxide solution. Proposed battery is suited for use at temperatures as low as -40 to -50 °C.

EFFECT: ability of battery normal operation at sub-zero temperatures.

2 cl, 1 tbl

Description

The claimed invention relates to the electrical industry and can be used in the manufacture of sealed nickel-cadmium batteries with tissue separation.

A known method of forming a sealed alkaline battery (AS No. 1304685, CL. H01M 10/28, 1995) by conducting charge-discharge cycles in an electrolyte volume equal to 17-19 free battery volumes. In such an electrolyte volume, the amount of carbonates remains within the normal range (up to 10 g / l), which makes it possible to reuse it. In this case, the amount of carbonates in the electrolyte during its reuse reaches 24.8 g / l.

The disadvantage of this method is that the presence of a significant amount of carbonates in the electrolyte when it is reused leads to an increase in the freezing temperature of the electrolyte.

The closest in technical essence and the achieved effect to the claimed is a method of manufacturing a sealed nickel-cadmium battery of high energy consumption (patent RU No. 2128870, Cl. Н01М 10/34, Н01М 10/26, 1999), including assembling a package of electrode plates with separation positive and negative electrodes with separation material, block sediment in the battery case, filling the battery with electrolyte and conducting forming charge-discharge cycles. After installing the separated electrode block in the casing, it is poured with an aqueous solution of caustic lithium with a concentration of 50-110 g / l, impregnated in a vacuum and charged, after which the solution of caustic lithium is drained, filled with an aqueous solution of caustic potassium with a concentration of 300-350 g / l with the addition of caustic lithium 15-35 g / l and conduct charge-discharge cycles. This method allows to reduce the loss of capacity during sealing.

The disadvantage of this method is the inability to ensure battery operation at temperatures below -30 ° C.

The aim of the invention is to ensure the operability of a sealed alkaline battery at low temperatures (up to -40 ° C-50 ° C).

The solution to this problem is achieved by the fact that in the method of manufacturing a sealed nickel-cadmium battery, comprising assembling a package of electrode plates with separation of positive and negative electrodes by a separation material, depositing a block into a battery case, filling the battery with electrolyte, conducting forming charge-discharge cycles and replacing the electrolyte, the formation in the aqueous solution of caustic potassium with a concentration of 240-320 g / l and in the aqueous solution of caustic potassium with a concentration of 300-350 g / l with the addition of caustic lithium 15 -35 g / l is carried out in a charge-discharge-charge sequence and the electrolyte is drained at the end of the charge under current, and the formation of caustic lithium in an aqueous solution with a concentration of 100-110 g / l is carried out in a discharge-charge-discharge sequence and the electrolyte is drained at the end discharge. In this case, prior to the formation of caustic lithium in a solution, exposure is carried out for 10-15 minutes.

The claimed method of manufacturing a sealed Nickel-cadmium battery, providing performance at low temperatures (up to -40 ° C-50 ° C), is implemented as described in the example.

Example. The formation of the battery type NKGK-15D. The battery is formed by a charging current of 4 A, a discharge current of 2 A at a charge time of 16 hours, and a voltage of up to 1 V. The nickel-cadmium battery, consisting of blocks of oxide-nickel and oxide-cadmium plates, separated from each other by tissue separation and placed in a metal case, pour electrolyte - an aqueous solution of potassium hydroxide with a concentration of the latter 300 g / l. The electrode block is impregnated under vacuum, after which the battery is formed by charge-discharge cycles with a message when the charge is about 150% of the nominal capacity as follows: charge-discharge-charge is formed in the sequence and 15 minutes before the end of the second charge, the potassium electrolyte is drained from the battery under charging current. After that, an aqueous solution of caustic lithium with a concentration of 100 g / l is poured into the battery, it is held for 10-15 minutes and the battery is switched to discharge. After the formation of caustic lithium in an aqueous solution in the discharge-charge-discharge sequence, lithium electrolyte is drained at the end of the last discharge. Then pour potassium lithium electrolyte (300 g / l KOH and 30 g / l LiOH) and carry out the formation of a charge-discharge-charge sequence. At the end of the last charge, the excess electrolyte is drained under current. After this, the formation is completed by discharge. Then, a potassium-lithium electrolyte is added to bring its amount to 0.45 ml per 1 cm ^{3 of the} electrode block (including separation material), a carbon electrode is introduced, the battery is sealed, and the container is tested in a sealed form.

Table 1 shows, for comparison, the characteristics of the experimental data obtained as a result of testing the NKGK-15D batteries made by the claimed technology and the characteristics of the NKGK-15D batteries in a standard version.

The capacitive characteristics of the NKGK-15D batteries manufactured by the proposed method were determined at negative temperatures after charging with a current of 1.0 A. The charging time is 17 hours, but up to a voltage of no higher than 1.55 V at a temperature of 20 ± 5 ° C. Discharge mode: current 3.0 A up to voltage 1 V with guarantees for capacity when discharging up to 1.0 V.

Table 1.
Discharge characteristics of a standard battery NKGK-15D and a battery manufactured by the claimed method Temperature at discharge, ° С Average discharge voltage, V The given capacity of the battery manufactured by the claimed method And · h % to nom. (15A · h) for a battery manufactured by the claimed method Remote battery capacity as standard, Ah +20 1.24 15.7 105 15.0 -twenty 1.18 11.9 79 6.0 -thirty 1.14 9.5 63 3.0 -40 1.00 5,0 33 -fifty 0.9 4.0 27

From the data given in the table it can be seen that with decreasing temperature, the value of the given battery capacity in the standard version decreases faster than that of a battery manufactured by the claimed method. Moreover, the standard battery does not work at a temperature of - 40 ° С-50 ° С. The claimed method of manufacturing a sealed Nickel-cadmium battery leads to an increase in the delivered capacity at low temperatures by more than 3 times. Thus, the claimed sequence of proposed technological operations ensures the performance of an alkaline sealed battery at low temperatures (up to -40 ° С-50 ° С).

Claims (2)

1. A method of manufacturing a sealed nickel-cadmium battery, comprising assembling a package of electrode plates with separation of positive and negative electrodes by separation material, depositing a block into a battery case, filling the battery with electrolyte, conducting forming charge-discharge cycles and replacing the electrolyte, characterized in that the formation of in an aqueous solution of caustic potassium with a concentration of 240 ÷ 320 g / l and in an aqueous solution of caustic potassium with a concentration of 300 ÷ 350 g / l with the addition of caustic lithium 15 ÷ 35 g / l charge-discharge-charge and drain the electrolyte at the end of the charge under current, and the formation of an aqueous solution of caustic lithium with a concentration of 100 ÷ 110 g / l is carried out in the discharge-charge-discharge sequence and drain the electrolyte at the end of the discharge. 2. The method according to claim 1, characterized in that prior to the formation of caustic lithium in the solution, an exposure is performed in the electrolyte for 10-15 minutes.