Influence of ambient temperature on lead-acid battery

Among all the environmental factors, temperature has the greatest influence on the charging and discharging performance of lead-acid batteries.

1. Influence of temperature on internal resistance: When the battery is powered off at the ambient temperature of 0 ° C to 30 ° C, the internal resistance of the battery decreases with the increase of temperature. On the contrary, when the battery temperature decreases, the internal resistance of the battery increases gradually, and the internal resistance of the battery changes linearly with temperature. So the battery discharge working temperature in the range of 0℃-30℃ electrolyte conductivity is good, Similarly, the diffusion speed of hydrogen ions and sulfate ions in the electrolyte to the active material is also high. Not only the concentration polarization effect is improved, but also the electrode reaction speed is increased, The effect of electrochemical polarization is further improved, so the battery discharge capacity is increased.
2. Influence of temperature on capacity: at different temperatures, the viscosity of sulfuric acid solution will be different. For example, below 0℃, the temperature keeps decreasing, and the resistance of sulfuric acid solution keeps increasing, aggravating the influence of electrode polarization, and the capacity of battery will be significantly reduced.
3. The impact of temperature on charge and discharge: repeated discharge and low voltage constant voltage charging cycle, the initial battery due to heat conduction, so the temperature is not high, if repeated charge and discharge cycle, electrolyte temperature will be very high. If charged at low temperature, the diffusion current density decreases significantly, while the exchange current density does not decrease much, so the concentration polarization intensifies, which leads to the reduction of the charging efficiency. On the other hand, the saturation of lead sulfate in the last discharge at low temperature increases the reaction resistance of battery charging and discharging, thus further reducing the charging efficiency.
4. Influence of temperature on battery life: If the temperature is too high and exceeds 45 ° C, the chemical balance in the battery will be destroyed, leading to side reactions. When the temperature rises above 45℃, the performance of rechargeable battery materials will degrade at high temperature, and the battery cycle life will be greatly shortened.