If a battery does not seem to charge or perform as well as it once did, it may be for one or more of the following issues: There may be a problem with the charging system. While the charging system is in operation, it will begin putting out approximately 13.8 -14.6volts. The vehicle electrical system may have a short circuit or current drain The terminals on the battery are not properly tightened There may be a problem with the battery itself so if you have verified that it is not a parasitic drain, and the battery is losing power within 1-7 days, then contact EarthX. Do not continue to attempt to charge or use a battery that will not hold a charge as it might indicated cell failure and continued use can cause cell rupture, smoke and even fire.