How to Use Your Lithium (LiFePO4) Battery Charger

1. How to Connect the Charger to Your Battery

Single Battery Setup:

  • To charge one battery, connect the positive (+) cable from the charger to the positive terminal of the battery and the negative (-) cable to the negative terminal.

Multiple Batteries in Parallel:

  • Parallel wiring means connecting the positive terminals of multiple batteries together, and the negative terminals together. This configuration keeps the voltage the same but increases the battery system's total capacity (Ah).
    • Example: If you connect two 48V 60Ah batteries in parallel, the total voltage remains 48V, but the total capacity increases to 120Ah, giving you more run time.
  • To charge batteries connected in parallel, connect the charger’s positive cable to the positive terminal of one battery and the negative cable to the negative terminal of one battery—since all the positives and all the negatives are connected, the charger will charge the entire group.

Multiple Batteries in Series:

  • Series wiring involves connecting the positive terminal of one battery to the negative terminal of the next. This increases the total voltage while keeping the capacity (Ah) the same.
    • Example: If you connect four 12V 100Ah batteries in series, the total voltage increases to 48V, while the total capacity remains 100Ah.
  • To charge batteries connected in series, connect the charger’s positive cable to the positive terminal of the first battery in the series, and the negative cable to the negative terminal of the last battery in the series.

2. Basic Operation

When using our Lithium (LiFePO4) battery charger, here's what you can expect:

  • When you first plug in the charger to a power outlet, the light will flash red and green. This means the charger is ready and looking for the battery.
  • Once it senses the battery, the charging process will start. The light will flash red, and you'll hear the fan running. This indicates the charger is in the deep charge stage, where it is working to restore the battery to full power.
  • During the deep charge stage, the light will continue flashing red as the battery is charged.
  • As the battery nears full charge, the light will change to flashing yellow, signaling the "Finishing Charge" stage, where the charger safely tops off the battery.
  • When the battery is fully charged, the light will turn solid green and remain green until the charger is disconnected or unplugged. The table below shows the Charging Stage Voltages. The charger will show as fully charged at the maximum charge complete voltage unless the BMS triggers “fully charged” at a lower voltage.

Charging Stage Voltages

Charger Style

Finishing Charge Starting Voltage

Maximum Charge Complete Voltage

12V

13.8V

14.6V

36V

43.0V

43.8V

48V

57.5V

58.4V

72V

87.0V

87.6V


If the charger is not operating as described, please reach out to us by clicking Contact Us.

3. The Role of the Battery Management System (BMS)

Your battery’s Battery Management System (BMS) plays an important part in the charging process. The BMS protects the battery from conditions like overcharging, undercharging, or overheating. It monitors the battery's state and can interrupt the charging process if something goes wrong.

BMS-Related Issues to Watch For:

  • Charging doesn’t start: If the charger doesn’t detect the battery or the charge won’t begin, the BMS might be in protection mode. This can occur if the battery is deeply discharged (i.e., the battery’s charge is very low) or if the battery is too cold or too hot.
  • Charging stops unexpectedly: The BMS may stop charging if it detects an imbalance in the battery cells or excessive heat.
  • Full charge not reached: The BMS could limit the charge to prevent overcharging if it detects potential risks.

If you encounter any of these issues, try to resolve the conditions causing the BMS to trigger (e.g., jump-start the battery out of protection mode, balance the cells, move the battery to a more stable temperature). If the problem persists, you may need to reach out to the battery manufacturer.

4. Important Safety Tips

  • Make sure your connections are secure before starting the charging process.
  • Check that your battery system’s specifications are compatible with the charger, whether you’re using a single battery, or wiring in parallel or series.
  • Never mix different types of batteries in the same charging setup (e.g., lithium and lead acid).
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