What to do if the battery doesn't charge, charger doesn't see the battery for 2 reasons: low voltage on it or triggered thermal protection.
Step 1: Measure the Voltage on the Battery
Step 2: If the Battery Has at Least Some Voltage.The Battery Can Be Put in Parallel With Another Working Battery.
10 seconds will be enough.
Step 3: Еhe Voltage on the Battery Has Increased, Now You Can Try to Put It on Charge.
But if the charger does not react again, the operation must be repeated
Step 4: And Repeat Until the Battery Starts Charging
Step 5: If the Battery Voltage Is 0, Thermal Protection Has Tripped
Step 6: the Membrane Under the Positive Contact Arched From the Pressure Inside the Battery
Step 7: After Returning the Membrane Back, the Battery Has Came to Life
Step 8: Then You Need to Do the First Operation and Now the Battery Is Working
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