Battery Failure Indicators

• The usable time after recharging is shortened.
• The battery becomes unusually warm during a rechargecycle.
• The battery becomes unusually warm during phone use.
• The battery case often is swollen. This is detectable by feeling and viewing the inside/phone-side of the battery case. Also, when the battery is placed inside/phone-side down on a flat, smooth surface, it will rock and will sustain a spin motion. The case of a healthy battery is flat and will not sustain a spin motion.
• The battery develops a hard spot. This is detectable on the inside/phone-side surface of the battery by gently pinching about the surface between one's fingers.

Tips

• Regardless of how well you care for your battery, it will die eventually. When it does, you may be able to have it refurbished by sending it to the manufacturer or bringing it back to the retailer. If it cannot be refurbished, or if you just want to get a new battery, be sure to recycle it, either by returning it to the manufacturer or retailer, or by bringing it to a recycling center. Most major retail electronics stores have drop-off boxes for recycled phones.
• You should not have to turn off your phone to charge it. Most battery chargers deliver more than enough current to power your phone and charge it at the same time. Doing so will not lengthen the charge time, and leaving a phone on allows the user to be aware of its fuel gauge, so that you can remove it when the battery is full.
• When using a car charger, do not charge the battery when the inside temperature of your car is hot. Wait until the car has cooled before you plug in the phone.

Warnings

• Do not store a lithium battery with a very low charge for a long time, the battery monitor will draw a small current, which might cause a 'deep discharge' which may cause damage to the battery.
• Avoid cheap, knockoff chargers as they may cause excessive battery heating.
• When buying lithium ion batteries, be aware that oxidation begins at the time of manufacture, not the time of first use. As such, older lithium batteries will have reduced capacity (about 20% per year stored at room temperature). If you buy a battery at a clearance sale price, expect that you will get less life out of the cell phone.
• Never dispose of old batteries in the trash. Batteries contain toxic metals, and electronic waste from batteries and other electronic components is becoming a major problem. Improper disposal of toxic batteries is illegal in many jurisdictions.