What is a small sealed battery?
2022 Feb 28 By admin 0 comment

Small sealed batteries are referred to as small batteries, or sealed batteries, and their common appearance is generally rectangular, as shown in Figure 1.

What is a small sealed battery?
Figure 1 Outline of a small sealed lead-acid battery

1. The structure of a small lead-acid battery
The structure of small batteries is basically the same as that of large batteries, but the plates of small batteries are mostly made of lead-calcium alloy, and the plastic shells, positive and negative plates, separators (plastic separators), electrodes and other components are relatively small, usually only 3. 6 single cells, so the volume is small, the mass is small, the electrolyte is small, and the capacity is relatively small.

What is a small sealed battery?
Structure of a small lead-acid battery

The filling hole of the small battery is usually made into a convex shape and covered with a rubber sealing cap. However, the filling hole and rubber cap cannot be seen from the outside of the battery, and they are sealed inside by the plastic cover, and only two electrodes can be seen, so it is called a sealed battery.

2. Characteristics of small lead-acid batteries
Summarize the small battery, with the following characteristics.

(1) Safety in use: Small batteries are generally of a fully sealed structure, using high-performance separators and safety valves, so there is no acid mist gas discharged during use, and there will be no leakage even if they are inverted, thus preventing the equipment from being corroded.

(2) Maintenance-free: The acid mist gas generated when the small sealed battery is charged is not discharged from the body, but is absorbed by the electrode plate and reduced to the electrolyte. Therefore, the electrolyte generally does not decrease, and there is no need to check the liquid level during use. and add distilled water. This shows that the sealed battery does not need maintenance from the new start to the end of the scrap, so it is also called maintenance-free battery.

(3) High specific energy: The small sealed battery has compact assembly, excellent materials, small internal resistance, high energy density, and its high current emergency discharge performance is higher, and the power it can drive is higher than that of ordinary batteries of the same capacity. About 60% higher.

(4) Small capacity: Usually, the lead consumption of lead-acid battery plates is proportional to its capacity, about 40 g (A h) 50 g/(A h). This means that the heavier the battery, the greater its capacity. Small batteries are lighter and therefore have less capacity.

(5) Low single cell voltage: For commonly used lead-acid batteries, no matter what the capacity, quality, shape, or open type or sealed type, the rated voltage of the single cell is 2V.

(6) Long service life: Since the small sealed battery uses corrosion-resistant lead-calcium alloy to make the grid plate, the service life of the battery is improved. If the floating charge is only used for emergency power backup, its life can be as long as 3-5 years.

If the cycle charge and discharge are used normally, it can reach more than 300 times.
(7) Storage resistance: Since the lead-calcium alloy is used instead of the traditional lead-jin alloy to make the pole plate, the self-discharge is very small, which is suitable for long-term placement. Generally, it does not need to be recharged within 6 months of storage at room temperature.

3. Performance parameters of small sealed square lead-acid batteries
The performance parameters of the two lead-acid batteries are listed in Table 1.

ParameterRated voltage
Rated capacity
Charge voltage


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Table 1 Performance parameters of two small sealed lead-acid batteries