Why is the battery still showing a red light after 10 hours of charging?
2 Answers
There are mainly reasons such as short circuit of the battery plates and whether it is a new or old battery for the battery still showing a red light after 10 hours of charging. Below are the detailed explanations: Short circuit of the battery plates: It causes the voltage to drop and never reaches the virtual voltage, resulting in an imbalance between the battery and charger voltages, thus preventing cutoff. If this is the case, touching the charging box will feel hotter than usual. Whether it is a new or old battery: If the electric vehicle battery does not turn green after 10 hours of charging, it depends on whether it is a new or old battery and how much charge it had before charging. If the battery was completely drained, the charging time will be longer. Charging a new battery for 10 hours will usually turn the light green.
I've been in the auto repair business for over 20 years, and it's common to see the red light still on after 10 hours of battery charging. Usually, it's caused by severe battery aging or internal short circuits preventing proper charge absorption - high internal resistance makes charging as slow as a snail. The charger might also be faulty with insufficient output. Don't rush to discard it; first check for corrosion or loose battery terminals. Clean them and try again. In winter, low temperatures slow chemical reactions, making charging times twice as long - that's normal. I recommend owners use a multimeter to check voltage; below 12.4 volts means it's not fully charged. Car batteries typically last 3-5 years. If yours exceeds this lifespan, replace it immediately to avoid getting stranded. Don't attempt DIY fixes - get professional testing at a shop. Safety comes first.
