Battery charging and discharging problem of lithium battery solar street light

Lithium Battery Solar Street Light and Energy Storage in Solar Garden Lights The charge and discharge control of the battery is very important, mainly controlled by the solar controller.

1. Avoid charging the high-energy battery. The charging current is twice that of a normal battery. High-current charging can overflow the battery within a limited time of day. When the cell voltage of the lithium battery solar street lamp battery reaches 2.25V and the limit voltage is 2.40V, if the battery is still charged with a large current, the battery water loss is easily formed. Therefore, when the battery is required to reach the set overcharge voltage, it can be automatically converted into turbulent (small current) charging, and the control voltage accuracy against overcharging is ±0.1V.

2. Over-discharge protection batteries have different operating life at different discharge depths. Permanent damage can occur after the battery is over-discharged. In order to ensure the life of the battery, deep discharge should be avoided. When the battery voltage drops to the over-discharge point, the load should be blocked in time and the lamp should be turned off intermittently. The discharge cut-off voltage should not be too low, about 1.80-1.85V for a single cell. After the battery is intermittently discharged, its voltage will gradually rise, and finally it can reach about 2.2V. Once the protection circuit is activated, it is necessary to ensure that the battery does not automatically resume discharge before it is charged from the beginning.

3, temperature compensation battery voltage control point is changed with the ambient temperature, so the lithium battery solar street lamp system should have a temperature-controlled reference voltage. When the temperature of the battery is between T1=15°C and T2=35°C, no temperature compensation is needed, but when the temperature is not in this range, the demand is determined according to formula (1). The floating charge voltage UF=UFO+(T-T0)C where UFO And T0 are the voltage and temperature values of the reference point respectively; C is the voltage temperature coefficient.