How to Fix a Lithium Ion Battery That Won't Charge — Charging Fix

Quick answer

• Ensure the battery is warm enough to charge; lithium-ion batteries refuse to charge below ~32°F (0°C).
• Check for visible damage on the battery pack; swollen or corroded packs should not be used.
• Verify that you are using the correct charger for your Hercules battery model.
• If the charger shows a fault LED pattern, consult the user manual for troubleshooting guidance.

Symptoms

When your Hercules lithium-ion battery won't charge, you may notice several symptoms:

• The charger LED may be blinking red or showing a solid red light, indicating a fault or charging issue.
• The battery may not power your tools at all, or it may power them for only a brief moment before shutting down.
• You might hear no sound from the charger, or it may emit a clicking noise, which can indicate a connection issue or a fault in the battery.
• If the battery is cold, it may not show any signs of charging, as the battery management system (BMS) locks out charging to protect the cells.

Quick checks

Before diving into deeper troubleshooting, perform these quick checks:

1. Temperature Check: Ensure that the battery is above 32°F (0°C). If it's cold, allow it to warm up before attempting to charge.
2. Visual Inspection: Look for any signs of physical damage, such as swelling, punctures, or corrosion on the battery terminals.
3. Charger Compatibility: Confirm that you are using the correct charger for your Hercules battery. Using an incompatible charger can lead to charging failures.
4. Connection Check: Ensure that the battery is seated properly in the charger and that there is no debris or dirt obstructing the connection.
5. Battery Age: Consider the age of the battery. Lithium-ion batteries typically last 2-3 years under normal use. If your battery is older, it may be time to replace it.

Step-by-step fix

1. Remove the Battery: Before performing any work, always remove the battery from the tool to avoid accidental activation.
2. Inspect the Battery: Examine the battery for any signs of damage. If you see swelling or corrosion, do not attempt to charge it.
3. Warm the Battery: If the battery is cold, place it in a warm area (above 32°F) for at least 30 minutes. This allows the BMS to reset and may enable charging.
4. Check the Charger: Plug in the charger and observe the LED pattern. For the Hercules charger, refer to the user manual for specific LED behavior. If it shows a fault, the charger may need to be replaced.
5. Test Charging: Reinsert the battery into the charger and check the LED indicator. A steady red light typically indicates charging, while a green light indicates a full charge.
6. Try a Different Charger: If possible, test the battery with a different compatible charger to rule out a charger issue.
7. Replace the Battery: If the battery still does not charge, consider replacing it with a new one.

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If it still isn't working

If the battery still won't charge after following the above steps, consider the following escalation paths:

• Warranty Claim: Check if your battery is still under warranty. Hercules typically offers a warranty on their batteries, which may cover defects.
• Service Center: Contact Hercules customer service or visit an authorized service center for further diagnosis and repair options.
• Replacement: If the battery is out of warranty and cannot be repaired, purchasing a replacement may be the most practical solution.

FAQ

Why won't my lithium-ion battery charge?
Lithium-ion batteries may refuse to charge due to low temperatures, physical damage, or compatibility issues with the charger. Always check the battery's condition and the charger's LED indicators.

What should I do if my battery is swollen?
Swollen batteries are a sign of internal damage and should not be used. Dispose of them properly at a recycling center and replace them with a new battery.

Can I use a different brand charger for my Hercules battery?
Using a charger designed for a different brand may cause damage to the battery or charger. Always use the charger specified for your Hercules battery model.

How long do lithium-ion batteries last?
With proper care, lithium-ion batteries can last 2-3 years. Factors such as usage patterns, charging habits, and environmental conditions can affect their lifespan.

What is the best way to store my lithium-ion battery?
Store lithium-ion batteries in a cool, dry place and avoid extreme temperatures. If you won’t be using the battery for an extended period, charge it to about 50% before storage.