Lead-acid batteries are one of the more commonly used batteries. The commonly used lead-acid batteries are mainly divided into three categories:
1) Ordinary storage batteries; plates of ordinary storage batteries are made of lead and its oxides, and the electrolyte is an aqueous solution of sulfuric acid. Its main advantages are its stable voltage and low price; its disadvantages are its low specific energy (That is the electrical energy stored per kilogram of battery), its short service life, and its frequent maintenance.
2) Dry-charged storage battery: its full name is dry charged lead-acid battery, its main feature is that the negative plate has a high ability to store electricity, in a completely dry state, can save the amount of electricity obtained in two years, before using it, you just need to add electrolyte, and wait 20-30 minutes.
3) Maintenance-free storage batteries: due to its own structural advantages, the electrolyte consumption is very small, basically do not need to add distilled water during the service life. It also has the characteristics of shock resistance, high temperature resistance, small size and small self-discharge. The service life is generally twice longer than that of ordinary batteries. There are also two kinds of maintenance-free storage batteries in the market: the first one,the electrolyte is added at the time of purchase and no maintenance is needed in later use (adding replenisher); the another type is that the battery itself has been added with electrolyte and sealed, the user doesn’t need to add replenisher.