How Long For Dead Battery To Charge. Typically a modern phone batterys lithium-ion lifespan is 2 3 years which is about 300 500 charge cycles as rated by manufacturers. Can a completely dead battery be recharged.
If you charge it for 30 minutes and then hold the HOME and SLEEP buttons at the same time the phone should reboot unless the battery has failed completely. That means you have to start charging your dead car battery with a decent battery. Its battery is a 48-amp unit.
The second thing is that you can charge using a battery charger.
Long-time charging with low amps is the best for keeping the batterys lifetime long. You may need to hook jumper cables up to a really dead battery for 5 or 10 minutes to give it enough of a surface charge and then hook up the charger afterward. It can be low from lights being left on an internal failure extreme hot or cold temperatures a failing alternator long term storage without being used or any number of other reasons. After that the battery capacity will drop by roughly 20.
