SU841073A2 - Method of moulding and charging storage battery - Google Patents

Description

one

The invention relates to the operation of batteries, in particular lead batteries.

A known method for charging a battery, such as a lead, is by passing a high-density direct current through it with a periodic supply of short-duration discharge current pulses, the amplitude of which is determined from the condition that the voltage of the discharge pulses is 5-10% large EMF of the battery at the time of connecting it to an additional source.

. St. 628555 is known a method of forming and charging a battery with a constant smooth current of increased density with a periodic supply of short-duration discharge pulses, close in shape to sinusoidal, with an initial duration equal to the half-period of the natural frequency of the battery and regulated during charging in accordance with by changing the frequency response of the battery I2j,

However, this method of forming and charging does not regulate the choice of the amplitude of the discharge current pulses.

When solving the known methods of charging batteries, a recharge of the battery occurs, leading to a decrease in the efficiency of the charging process and the battery life.

The purpose of the invention is to increase the efficiency of the charging process and increase the service life of the battery.

0 batteries.

This goal is achieved by the fact that the magnitude of the amplitude of the voltage of the discharge current pulses is determined as the difference in voltage across the terminals of the charging battery and the total permissible voltage of the forcedly depleted battery under load.

In addition, the minimum permissible voltage of a fixedly discharged battery is set in the range of 0-0.5 V per cell.

 FIG. 1 is a schematic 5 diagram illustrating the proposed charging method; in fig. 2 shows current and voltage diagrams in a low battery circuit.

The circuit contains charge-discharge device 1, control system 2.

voltage sensor 3 and battery 4.

When forming and charging an accumulator battery with a smoothed constant current of high density, to increase the susceptibility of the battery, discharge current pulses are applied to the charge current, the parameters of which are chosen depending on the charging mode and battery size. One of the main criteria for reducing the charging time is the need to apply discharge pulses of the smallest possible duration and maximum amplitude.

However, the analysis of a battery as an active two-pole device indicates the existence of an optimal duration of discharge current pulses, equal to the half-life of the natural frequency of the battery, which varies during charging.

In choosing the amplitude of the discharge current pulses, there are no clear recommendations based on the electrochemical nature of the battery. The supply of short-duration current discharge pulses to a battery is a short-term forced discharge to its load, which is a 3.pd-discharge device. When an accumulator bat battery is discharged, it is not allowed to reset it or achieve zero voltage. In the practice of operating batteries, when discharged with their 5–10-hour current, the minimum voltage at the terminals of the discharged battery (under load) is of the order of 1 B per cell. In various recommendations and methods for testing batteries, the number 0.5-0.6 V per cell is indicated when the battery is discharged with a current of one hour. Consequently, the faster the battery discharge mode, the greater the reduction in voltage drop across the battery terminals, excluding the achievement of zero voltage and polarity reversal of the battery.

By knowing the frequency characteristic of the charged battery, the range of variation of the duration of the discharge pulses, equivalent to the time of the forced discharge of the battery and the allowable voltage decrease at its terminals in the range of 0-0.5 V, is determined. The indicated voltage is taken as support pr implementation of the method of charge.

When a battery is charged with a high-density current, the voltage on its clams is defined as the sum of its own emf increasing as the charge increases and the voltage drops from the flowing current. At the time of submission

discharge current pulses, the voltage at the terminals of the battery 4, controlled by sensor 3, is compared in control system 2 with a reference voltage equal to the minimum allowable discharge voltage, which is in the range of 0-0.5 V. Control system 2 produces a signal control, corresponding to the specified voltage difference, for the charge-discharge device 1, which forms it. pulse of discharge current of the required duration and amplitude (Fig. 2).

For example, for a lead-acid battery, the voltage at its terminals when charged with an increased current varies in the range of 2.7-3.5 volts per cell, while its specific resistance is 6-8-10 OMiM. Since the shape and duration of the discharge pulse per charge is consistent with the changed-i.e.M frequency characteristic of the battery, the latter represents a purely ohmic for the discharge pulse, and the n-th complex equivalent resistance. Consequently, the amplitude of the discharge impulbs of the current is determined by j. Uuq-Upofb Mwvn

is made by the formula and equal (V, B

25-100 amps per 1 Lh of battery capacity, which is kilo-amps when charging 40-100 Ah batteries and is quite large.

Thus, as the battery is charged, such as a lead-acid battery, its internal resistance decreases and the voltage at the terminals increases. These factors lead to an automatic increase in the amplitude of the discharge current pulses without polarizing the battery, which favorably reflects on the intensification of the battery charging process.

Claims (2)

1. Method of forming and charging the battery by author. St. No. 628555, characterized in that, in order to increase the efficiency of the charging process and increase the battery life, the magnitude of the voltage amplitude of the discharged current pulses is determined by the difference in voltage across the terminals of the charged battery and the minimum allowable voltage of the forced discharge Battery under load. 2. A method according to Claim 1, characterized in that the minimum acceptable voltage for a forcibly depleted secondary battery is installed in a range of 0-0.5 V per cell. Sources of information taken into account during the examination 1. USSR author's certificate No. 497660, cl. H 01 M 10/44, 1974. 2. USSR author's certificate It 628555, cl. H 01 M 10/48, 1977. but) and S)