Battery Inspection & BMS Cold Start Procedure for Rolls G-Series & S-Series LFP Drop-in Batteries

Safety Notice:

Perform all steps with caution. Wear heavy leather gloves and a face shield or appropriate eye protection. Complete all energized steps in a warehouse area with the battery placed on a cart or similar platform so it can be moved quickly if necessary.

1. Remove the Top Cover

• Remove the top cover of the battery by first removing the small plastic covers over the screws along the edge of the battery cover on all sides.
• Once removed, if the top must be fully disconnected, apply electrical tape to the internal BATT+ and BATT- terminals to prevent accidental shorting.
• Do not disconnect internal terminals unless absolutely necessary.

2. Visual Inspection

• Using a flashlight, inspect the interior for:
  • Cell damage
  • Electrolyte accumulation at the bottom of the case
  • Signs of gassing
• If electrolyte is present, it will have a strong, unpleasant odour.
• Inspect the yellow insulation boards for discolouration, which may indicate overheating or venting.

3. Regulated Power Supply Connection

(Warehouse only — see safety notice above)

• Connect a 12 V current-regulated power supply(NOT a charger):
  • Positive → Internal BATT+
  • Negative → Internal BATT-
• Power supply requirements:
  • Capability: 5–15 A
  • Preferred max capability: 10 A
  • Current limit set to a maximum of 8 A
     

Important:

• If smoke is observed, immediately disconnect the power supply and ventilate the area.
• Smoking should stop a few minutes after the power supply is removed.

4. Charging Behavior and Monitoring

• The power supply should initially peak near 8 A, then taper down as the cells begin charging.
• Keep a phone connected to the battery via the application during this process.
• Immediately discontinue chargingif:
  • Cell voltages spike abnormally
  • Temperatures rise rapidly
• Leave the power supply connected (if no issues occur) until battery voltage reaches 12.4–12.8 V.

At this point:

• The BMS should reconnect and wake up within 10-15 minutes.
• The battery should then accept charge from a standard battery charger.

5. Cell Voltage Verification

• Disconnect the power supply from the internal BATT+ and BATT- terminals.
• Observe individual cell voltages via the application:
  • If voltages rapidly collapse, the battery must be scrapped.
  • If voltages remain stable for 5–10 minutes, proceed.

6. Reassembly and External Charging

• Reinstall the top cover.
• Charge the battery using the external B+ and B- terminals with a charger or power supply.
• Leave the charger connected for at least 60 minutes in the absorption stage to allow cell balancing.

7. Cycling and Final Validation

• Cycle the battery 4–6 times.
• Ensure internal temperature does not exceed 45 °C at any time.
• If temperature exceeds this limit, or abnormal behaviour is observed, the battery has cell or BMS faults and must be removed from service.

Internal Layout: