RV Lithium Battery Not Charging: Complete BMS Reset & Troubleshooting

Tools & Parts Needed

Find these on Amazon: Digital Multimeter , Insulated Work Gloves , Safety Glasses

Recognizing the Signs

If you're experiencing this issue, you're not alone. Here's what's typically happening and how to address it.

What You Might Notice

When your Battle Born lithium battery shows 20% charge but won't accept power from shore or solar, the Battery Management System (BMS) has likely activated protection mode.

Root Causes

Battle Born lithium batteries have sophisticated BMS systems that protect against several conditions:

• Over-discharge protection - BMS may lock out charging if battery dropped below 10.5V
• Temperature extremes - Charging stops if battery is too hot (>140°F) or cold (<23°F, with charging typically disabled below 23°F and above 140°F)
• Overcurrent protection - High charging current from multiple sources can trigger protection
• Cell imbalance - Individual cells may be out of balance, requiring BMS intervention
• Voltage spike protection - Faulty charge controllers can send overvoltage

What to Grab

• Digital multimeter
• Insulated gloves
• Safety glasses
• Basic hand tools (wrenches/screwdrivers)
• Flashlight or headlamp

Your Action Plan

SAFETY WARNING: Before working on battery systems, ensure all power sources are disconnected. Wear safety glasses and insulated gloves. Never work alone on electrical systems. IMPORTANT: Before attempting a BMS reset, verify that underlying causes (temperature extremes, overvoltage from charge sources, or other protection triggers) have been resolved. The BMS will immediately re-enter protection mode if the root cause persists.

1. Disconnect shore power - Unplug your RV from the electrical hookup completely
2. Turn off solar controller - Switch your solar charge controller to OFF position or disconnect solar input
3. Disconnect battery terminals - Remove negative terminal first, then positive terminal from the Battle Born battery
4. Wait 5-10 minutes - This allows the BMS to fully reset and clear any protection flags
5. Check battery voltage - Using your multimeter, measure voltage across battery terminals (should read around 12.8V or lower at 20%)
6. Reconnect terminals - Attach positive first, then negative, ensuring tight connections torqued to manufacturer specifications (per Battle Born's specifications (see manufacturer documentation))
7. Restore power sources - Turn solar controller back on, then reconnect shore power
8. Monitor charging - Watch for charging indicator lights or voltage increase on your battery monitor

Situations That Need a Professional

Contact a certified RV technician or Battle Born's technical support if:

• BMS reset doesn't restore charging after multiple attempts
• Battery voltage reads below 10V
• You smell burning or see physical damage to battery
• Battery is excessively hot to touch
• Multiple error codes appear in the mobile app (on app-enabled models)
• Battery is still under warranty (DIY repairs may void coverage)

Battle Born offers excellent technical support at (855) 292-2831 and may provide remote diagnostics.