How to tell which golf cart lithium battery is bad

Here are some ways to identify a bad lithium golf cart battery:

• Check the voltage - A healthy lithium golf cart battery should read between 12.8V and 13.2V when fully charged. A reading below 12V likely indicates a bad cell.
• Inspect for swelling - Bulging or swelling of the battery case indicates gas buildup and internal damage. This usually means the battery needs replacement.
• Load test the battery - Use a battery load tester to apply a draw and simulate real-world use. A bad battery will show voltage drop or failure to hold charge.
• Monitor run time - Lithium batteries degrade slowly over time. Shortened run time between charges could indicate a failing battery.
• Check charge and discharge amps - Weak or unbalanced cells may charge/discharge at different rates than the rest of the pack. This flags a bad battery.
• Check fault codes - Many lithium batteries have built-in BMS systems to monitor health. Error codes point to issues.
• Check cell balances - A specialized tool can validate all cells are at equal voltage. Imbalances point to bad cells.
• Look for damage - Cracks, dents or punctures can compromise the battery enclosure and internals.