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4.1.9.
Charge Slower in Very Cold Conditions
If ambient temperature is below 39°F (4°C), reducing the initial charge current to no greater than 60A
until the batteries have had a chance to warm up is recommended before introducing the nominal
charge rate of 100A.
4.1.10.
Ensure Batteries Are at the Exact Same Resting Voltage Prior to Operation
When returning batteries into operation ensure they are at the exact same resting voltage (ideally
wait an hour or two to observe the resting voltage). They should all be at exactly the same low
voltage (all within 0.05V of each other) between 11.5V to 12.5V prior to initiating charging.
Alternatively, they can all be charged to exactly the same full voltage of 14.1 to 14.2V (batteries must
be within 0.05V of each other). Refer to 3.1 for more information.
4.1.11.
Ensure Parallel Rows of Batteries are Within 0.2V of Each Other
Where there are multiple strings of batteries in parallel, verify the voltage of each string of batteries to
ensure they are all within 0.2V of each other. If not, you will need to re-perform the charging step
found in 3.1. If the strings of batteries have too high of a voltage difference there is a risk that too
much current will flow from one string to the other and cause the BMS to shut the batteries down.
