Summer temperature is relatively high may be the battery water shortage, it is said that the dry battery do not add battery water in fact, the battery needs a little water, if there is no drum up the battery water is good, if the drum will be changed to a new battery. If you can still run, unplug after 6 to 8 hours to slow the rate of battery bulge and increase battery life.
Why are electric cars fully charged in winter?
Summer is always dissatisfied because the winter battery is used quickly, cold and easy to freeze, so it is soon full of the summer battery melted, so the charge is slow
If the battery dies, you can replace it with a new one