[[TitleIndustry]]

Lead-acid battery classification

Date:Jul 05, 2019

Battery and gel battery. Famous domestic brands include Shenyang Panasonic, Shanghai Haibao, Zhejiang Tianneng and Chaowei, and the colloidal battery has Huafu. These battery manufacturers have a wider battery coverage. Shenyang Panasonic's battery uses 11 plates, the initial capacity is not large, but the life is relatively long. Haibao uses 17 plates to take into account the initial capacity and longevity, while Tianneng and Chaowei have the largest initial capacity and the life expectancy is not as good as the former. Then the specific gravity of sulfuric acid, Panasonic is the lowest, Haibao is second, Tianneng and Chaowei are the highest. A battery having a low specific gravity of sulfuric acid has a poor initial capacity, but has a relatively long life, and the sulfuric acid has a high specific gravity.


In view of the fact that some car manufacturers have no or lack of battery inspection capability, the battery is tested by the "running circle" method. Such an inspection method causes some small battery manufacturers to improperly increase the specific gravity of the sulfuric acid of the battery and increase the amount of active material of the positive electrode plate (resulting in insufficient transition of the negative electrode of the battery and large water loss). Even reducing the number of plates to reduce costs. The life of such batteries is not long, and such batteries are common in the batteries of scooters. And such a scooter supporting such a battery is still exported, giving the impression of a bad Chinese product on the international market.


Q: What is the capacity of the battery?

A: The battery can be used in different conditions. In order to calibrate the capacity of the battery, the rated capacity of the battery is defined. The amount of capacity is the minimum amount of electricity that should be released when the battery is manufactured under a certain discharge condition. The unit is Ah (Ah).


The specified battery discharge conditions are: the current discharged by the battery, generally the discharge rate. The termination voltage of the discharge, the discharge current is different, and the termination discharge voltage is also different; the discharge temperature, the discharge capacity at the low temperature of the battery is small, and the discharge capacity is high at a high temperature. The discharge temperature is specified in order to unify the discharge capacity.


The discharge rate is the magnitude of the discharge current of the battery, which is the time rate and current rate.

The discharge time rate refers to the length of time that the discharge is terminated to a termination voltage under a certain discharge condition. According to the IEC standard, the discharge rates are 20 hour rate (20Hr), 10 hour rate (10Hr), 5 hour rate (5Hr), 3 hour rate (3Hr), 2 hour rate (2Hr), 1 hour rate (1Hr), 0.5 hour rate (0.5Hr) and so on.


As the battery is discharged, the terminal voltage of the battery will gradually decrease. The lowest voltage that is discharged at 25 ° C until it can be repeatedly charged again is called the discharge termination voltage. The discharge rate is different and the discharge termination voltage is also different. Generally, the termination voltage at a 10-hour rate is mostly 1.8V/single cell, and the termination voltage at a 2-hour rate is generally 1.75V/single cell. Below this voltage, although a little more power can be discharged, it is easy to form a capacity for recharging, so do not discharge below this voltage unless special circumstances.


The rated capacity of the battery is expressed by C. The battery capacity obtained by different discharge rates will be different. For example, the current value represented by the discharge current of 10 hours is: I10=C10/10=0.1C10, discharge current of 2 hours discharge rate The current value is: I2=C2/2=0.5C2, and the discharge current of the 1-hour discharge rate indicates the current value: I1=C1/1=1C2.


Q: What effect does the battery discharge current have on battery capacity?

Answer: The discharge current of the battery is different, and the capacity that can be released is also different. The larger the discharge current, the smaller the amount of electricity that can be discharged. For example, the electric current commonly used in electric bicycles is 5A, and the battery using the nominal 10Ah is a 2-hour rate discharge. If a 10-hour rate discharge is used, it can reach 12Ah. Thus, if the battery is nominally 2 hours, it should be 10 Ah, and if it is 10 hours, it is 12 Ah. Therefore, looking at the capacity of the battery depends not only on the capacity of the battery, but also on the discharge rate of the battery. The battery of an electric bicycle is often nominally 10Ah (2Hr), and the same battery can also be labeled 12Ah (10Hr) and 14Ah (20Hr). Another example. The 14Ah (2Hr) battery can also be labeled 17Ah (10Hr). Some batteries have a capacity of 20 hours, and the battery capacity is nominally large, but there is no significant change in battery capacity.

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