There are mainly four types of solar street lamp batteries currently used in the market lead-aid batteries,colloidal batteries,ternary lithium batteries and lithium iron phosphate batteries.
Currently,there are four types of solar street lamp batteries used in the market lead-acid batteries,gel batteries,ternary lithium batteries and lithium iron phosphate batteries.
1.Lead-acid battery .The phosphate of a lead-acid battery is composed of lead and lead oxide, and the electrolyte is an aqueous solution of sulfuric acid .The main advantages of lead-acid batteries are that the voltage is relatively stable,the price is relatively cheap,and the safety is high, the disadvantage is that the service life of lead-acid batteries is relatively short. and the volume is much larger than ordinary batteries, but because of its price advantage,it is currently in solar energy.The street lamp industry still
occupies a dominant position in the use.
2.Colloid battery it is equivalent to an upgraded version of a lead-aid battery. it is maintenance-free and requires little maintenance . It mainly replaces the sulfuric acid electrolyte with a colloidal electrolyte internally ,which has improved in power storage, discharge capacity safety performance and life; The full name of its temperature is used in a wider range. The gel battery can be used in the temperature range of-40℃65°C.The low temperature performance is better. In the northern cold regions or the tropical regions with higher temperatures,the gel battery is the best The choice, is seismic performance is also very good, can be safely used in a variety of harsh conditions,the service life is double or even more than ordinary lead-acid batteries.
3.Ternary lithium battery .There are many advantages of ternary lithium battery. It has high specific energy, small size,fast charging and high price. The number of deep cycles is about 500-800 times,the life is similar to that of gel batteries, and the temperature range used is-15℃-45℃.However,the ternary lithium battery also has drawbacks and poor safety. If the battery is not stable inside, and if it is a ternary lithium battery produced by an unqualified manufacturer, it is very likely that it will be possible during the overcharge process or in a high temperature environment.An explosion occurred.
4.lithium iron phosphate battery high specific energy, small size,fast charging,good stability, and wide temperature range, but the price is the highest among all batteries, At present due to its cost problem ,it has not been promoted on a large scale.Because of the lead-acid batteries or gel batteries used in most solar street lamp systems, we will introduce the maintenance of these two batteries:
1.To prevent overcharging
ln addition to external maintenance,the battery life of solar street lamps is also closely related to the accumulation generated inside. if the solar battery is overcharged,the internal temperature of the battery will increase step by step, and thermal runway will occur. If it is serious it may greatly shorten the life of the battery, or even make the battery scrapped. lf we want to prevent the battery from overcharging,we must provide the charging voltage value strictly in accordance with the manufacturer’s instuctions.
2.To prevent insufficient charging
In addition to preventing overcharging,solar cells must also prevent undercharging . lf the charging is not enough,it may be caused by the rack system’s problems or the voltage is too low. Frequent under-charging will reduce the number of battery cycles and shorten the life of the battery.
3.To prevent over discharge
The discharge depth of the battery is closely related to the number of battery design charge-discharge cycles (service life) In terms of proportion ,if the depth of discharge is 10%,the number of cycles is 10,00 0.,and when the depth of discharge is 70%,the number of cycles is only 500. The greater the depth of discharge,the fewer the number of cycles.
lf the over-discharge is serious,the life of the battery will be shorter. lf it is serious,it may cause the battery to be unable to be activated to the best state, or even be scrapped at once. In order to prevent this battery from over-discharging ,it is necessary to install an additional BMS system in the battery.so that he voltage of the battery can be adjusted,and the voltage and current between the batteries can be balanced.
4.Control the ambient temperature
The extremely high temperature environment will shorten the life of the solar battery by half, so the temperature control of the solar cell is very important.The battery has a longer service life in normal temperature weathers, and the battery suffers in high temperature weather .If the environment is relatively harsh and there are extreme low or high temperatures.
lt is best to use a gel battery with a wide temperature range when choosing a battery.
