Electric car batteries recharge quickly, but are not durable.
If it suddenly becomes like this, it is likely that a single battery in the battery pack is not working, or it may be that too much water is lost, and the capacity is seriously reduced by vulcanization. After riding to no power, open the shell to test the voltage of each single battery, if there is less than 10.5 volts, then replace it, do not change a new, change a physical performance is still good (that is, the voltage is above 10.5 volts). After the replacement, add a water, stand for 24 hours, absorb the excess electrolytic current, start charging, you can.
However, because of the charge and discharge process, more or less there will be vulcanization phenomenon, for a long time, it will generate hard lead sulfide crystals, reduce the active substances in the electrolyte, resulting in a decrease in capacity, if conditions are available, you can buy a piece of lead acid battery capacity restorer in the local parts store or on Taobao to prevent and remove plate vulcanization, and remove these sulfide crystals. Restore to the active substance, so that your electric car battery will return to normal.
If the battery of an electric vehicle is fully charged for an hour, it proves that the battery's storage capacity is full. In the case of late battery without power, an hour full charge proves that the battery has a problem, the battery has begun to expand.