If you’re experiencing issues with your lithium battery not charging, there are a few easy troubleshooting tips you can try. Let’s dive in and see what might be causing your power problems and what you can do about it.

How Do Lithium Batteries Charge?

Lithium batteries require a BMS (battery management system) to monitor the status of the batteries. This vital piece of equipment helps ensure that the batteries only charge when the conditions are safe for charging. No matter how you’re charging your lithium batteries, the BMS should prevent charging when temps are below freezing, unless the batteries are heated.

Because lithium batteries can charge quickly and efficiently without long absorption charge requirements, many owners choose to use solar panels to charge their lithium batteries. However, you can also charge through a vehicle alternator or shore power. Depending on the size of your battery bank, you can save hours of charging time by choosing lithium batteries over lead-acid options.

Why Is My Lithium Battery Not Charging?

Unfortunately, if your lithium battery is not charging, several things could be causing the issue. The troubles could range from a damaged battery to external complications that have nothing to do with your lithium battery. It will take some trial and error and a bit of troubleshooting to get to the root of the problem. 

5 Easy Troubleshooting Tips for Lithium Batteries

If you’re experiencing issues with your lithium batteries, here are a handful of things you should check first. These are some of the easiest and most common places to start, and just about anybody can check them.

1. Make Sure Your Charger Is On and Working

The most common cause of a battery bank not charging is that the charger itself has quit charging. This could be due to a simple switch or fuse or as complicated as a damaged charger. Before going further in your diagnostics, make sure your charging source is working. Here are some areas to check for the major charging types.

• Shore Chargers – These need power from the grid so make sure the breaker is not tripped and the unit has power. Check that the switch is on and if it has a remote panel or switch that it is on as well. Sometimes these units also need to be programmed for the appropriate battery so be sure its properly programmed.
• Solar Chargers – Make sure the panels have full sun and are connected properly to the charge controller. Check fuses or breakers attached to the charge controller, and if it has a screen or is a smart controller, check to be sure it’s enabled.
• Alternator Chargers – Most of the time an alternator charge controller or DC-DC controller sits between the alternator and the batteries. This unit detects when an engine is running and starts charging. Settings on these units can be complicated, but you need to make sure the voltages are set correctly for the vehicle and battery bank its charging. These systems should also include a plug, fuse or switch to turn it on and off so be sure they are properly connected.
• Generator Chargers – Generator charging of lithium batteries is almost always accomplished with the same charger used for shore charging. If the batteries are charging on shore and not the generator then the transfer switch that automatically transfers power is to blame. Also, check that the breaker on the generator is not tripped and connections are good if its portable. There is also the possibility that the charger does not like the power output from the generator. On victron chargers a setting “enable weak AC charging” sometimes needs to be enabled.

If you’re unsure whether your charger is working, you will need to try using a meter to test it, and we will discuss that a little further down.

2. Double Check Your Connections

One important and easy thing to check when your lithium battery isn’t charging is your connections. Simply wiggle the wires and look for any loose connections that need tightening. This includes the connections to the battery and any other connections in your electrical system to your charging infrastructure.

It might surprise you that a slightly loose connection can cause problems, including problems charging your batteries. Tighten loose connections and test your system again to see if that fixes your problems.

2. Use a Clamp-On Ammeter and Volt Meter

If everything seems okay so far but you’re still unsure whether your charger is working, the next step is to measure what’s actually happening in the system. A clamp-on ammeter and volt meter are the safest and easiest tools to use here. They let you check both voltage and current without disconnecting wires.

Step 1: Check Voltage at the Batteries

• Set your volt meter to DC voltage.
• Place the probes on the positive and negative battery terminals.
• A fully charged lithium battery should rest around 13.2–13.4V.
• When charging, you should see a voltage higher than resting — typically 14.2–14.6V depending on your charger.
• If the voltage never rises above the resting level, your charger may not be delivering power.

Step 2: Test Voltage at the Charger

• Next, measure the voltage at the output terminals of your charger or charge controller.
• Compare this reading with what you saw at the battery.
• If the charger shows proper charging voltage (above 14V) but the battery side does not, there may be a loose connection, blown fuse, or tripped breaker between the charger and the battery.

Step 3: Measure Current Flow with a Clamp-On Ammeter

• Clamp the meter around the positive wire running from the charger to the batteries.
• A positive amp reading means current is flowing into the batteries (charging).
• A negative amp reading means current is flowing out (discharging).
• If the reading is zero when the charger should be active, then the charger isn’t delivering power.

Step 4: Check Current at the Battery Bank

• Clamp around the main positive cable coming off your battery bank.
• Compare readings to ensure all expected current is reaching the batteries.
• If you have multiple batteries, clamp around individual interconnects to confirm current is balanced. Each battery should contribute roughly equally.

By combining these voltage and current checks, you can quickly narrow down whether the charger, the wiring, or the battery bank is at fault. If the batteries are getting a higher charge voltage but not charging it is most likely the BMS inside the battery that is causing problems and may need professional repair.

3. Get the Battery Out of Low Voltage Disconnect Mode by Resetting It

Some batteries, including Battle Born batteries, have a low-voltage disconnect feature built into the BMS. This is a safety feature designed to protect your batteries and help ensure they last as long as possible. The low-voltage disconnect mode typically kicks in when a battery reaches 10V, and it’s important that you charge your battery as soon as possible. Within five days is best.

The only way to get a battery out of low-voltage disconnect mode is by resetting it, which means charging it. You’ll need to plug into shore power or alternator power or get a charge from solar panels. If you can, charge them back up to 100% and allow the batteries to balance all of the cells.

4. Make Sure You Are Using an Appropriate Charger

If you just dropped in a lithium battery with your existing electrical system, there’s a good chance your charger is insufficient. Lithium batteries can accept substantially more power compared to other types of batteries. This is why they charge faster.

You may need to upgrade your charger or adjust its settings to accommodate your lithium batteries. Check with the documentation that came with your charger and your batteries to ensure they’re compatible. 

5. Call Battle Born Batteries’ Customer Service Line for Help

When in doubt, give our customer service line a call at (855) 292-2831. Our customer service department has experience helping troubleshoot battery systems, even over the phone. If we can’t help fix your problem, there’s a good chance we can point you in the right direction of an expert who can.

How Do I Know if My Lithium-Ion Battery Is Damaged? 

If a lithium battery has experienced serious damage, the internal BMS won’t allow the battery to do anything. It won’t accept a charge or provide any power. This is a safety mechanism that keeps you, your vehicle, and your family safe from anything that might not be wired right in your rig. That could be why your lithium battery isn’t charging.

You could have permanently damaged your battery if you’ve ever charged or discharged your battery outside of the recommended specifications or if your lithium battery has been in an accident. If you’re experiencing these types of issues, then you’ll want to have your battery inspected to understand the root of the problem. Call us anytime to discuss any Battle Born Battery questions!

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Want To Learn More About Electrical Systems and Lithium Batteries?

We know that building or upgrading an electrical system can be overwhelming, so we’re here to help. Our Reno, Nevada-based sales and customer service team is standing by at (855) 292-2831 to take your questions!

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