When should temperature be considered during the equalization charge?

Understanding Battery Temperature’s Impact

Temperature affects the battery’s state of charge (SOC), internal resistance, and capacity. When batteries are charged at high temperatures, they can absorb more charge, but their internal resistance increases, reducing the overall system’s efficiency. Conversely, charging batteries at low temperatures can slow the charging process and reduce capacity. As a result, temperature must be considered when planning an equalization charge to avoid over- or under-charging specific batteries.

Equalization Charge Temperature Guidelines

The following temperature guidelines should be followed when performing an equalization charge: For a temperature range of 15°C to 35°C (59°F to 95°F), the equalization charge can be conducted at the standard voltage (e.g., 14.4V for a 12V battery bank). However, for temperatures above 35°C (95°F), the equalization charge voltage should be reduced by 0.5V to 1V to prevent over-charging. Conversely, for temperatures below 15°C (59°F), the equalization charge voltage should be increased by 0.5V to 1V to compensate for the reduced charge acceptance.

Practical Implementation

To incorporate temperature into the equalization charge process, use a temperature sensor to monitor the battery bank’s temperature. Once the temperature range is known, adjust the equalization charge voltage accordingly. For example, if the temperature is 40°C (104°F), the equalization charge voltage could be reduced to 13.4V to prevent over-charging. By considering temperature during the equalization charge, you can ensure a safe and effective process that maintains the health and longevity of your battery bank.