Battery discharge current. Generally speaking, it is the discharge rate. There are time rate and current rate for the discharge current of the battery. Discharge time rate refers to the length of time from discharge to termination voltage under certain discharge conditions. According to IEC standards, the discharge rates are respectively 20 hour rate, 10 hour rate, 5 hour rate, 3 hour rate, 2 hour rate, 1 hour rate, 0.5 hour rate, etc. The rated capacity of the battery is expressed in C. The capacity of the battery obtained at different discharge rates will be different.

The difficulty of sealing lead-acid batteries is the electrolysis of water during charging. When the charging reaches a certain voltage (generally above 2.30V/cell), oxygen is released on the positive electrode of the battery, and hydrogen is released on the negative electrode. On the one hand, the released gas brings out the acid mist to pollute the environment, on the other hand, the water content in the electrolyte decreases, so it is necessary to add water for maintenance at intervals.

Pb-Ca-Sn alloy grids are used in lead-acid batteries, and hydrogen evolution inhibitors are added to the negative plates. The wet charging technology is widely used in the battery industry. After limiting the charging voltage, these batteries can be considered maintenance-free. However, their service life is very dependent on the charging conditions that need to be strictly observed, in particular the limitation of the maximum charging voltage. Battery engineers and producers are looking for ways to recycle into water the H2 and O2 released during battery charging and overcharging. In this way, the problem of water loss can be solved.