Maintenance-free battery (life of 2-4 years)

　　The advantage of maintenance-free batteries is that compared with lead-acid batteries, they consume very little electrolyte, do not need to be supplemented with distilled water during use, are resistant to high temperatures, are small in size, and have low self-discharge. Of course, since there are many advantages, the price is not too cheap, about twice that of lead-acid batteries. The service life is the same as that of lead-acid batteries, and the replacement cycle of maintenance-free batteries is about 3 years under normal conditions.

　　General lead-acid battery (2~4 years of life)

　　The lead-acid battery is a general-purpose battery. The electricity is composed of lead and lead oxide, and the electrolyte is an aqueous solution of sulfuric acid. Generally speaking, this kind of battery has the advantages of low price and stable voltage, but the battery life is relatively short and the maintenance time is long. Under normal use, the service life is about 3 years, and the charging and discharging cycle is about 300-500 times.

　　Of course, in order to meet the limitations of this type of battery and extend its service life, the electrolyte level should be checked every 10,000 kilometers, and the electrolyte level should always be maintained at the correct level even after charging. Can extend the service life of the battery to a certain extent. However, most 4S stores have stopped this additional service.