I had to buy some new batteries for our cellphones this week, after the old ones started to undeniably show their age by failing to hold a decent charge.
A trip to Froogle turned up Cellphone Battery Warehouse, and a few minutes later the batteries were ordered. (Bear in mind, I have no connection with either, except as a user of one and a satisfied customer with a single transaction of the other.)
Besides the batteries, Cellphone Battery Warehouse included a great little instruction sheet with the batteries. For those of the Survivalist persuasion, it's full of little nuggets of good information.
There's a lot of contradictory information about batteries, and I was grateful to get some information from folks who deal with them on a daily basis.
Slightly edited and reworded, here are their words 'o wisdom on Ni-MH (nickel metal hydride) and Li-Ion (Lithium Ion) batteries:
Store batteries in a cool, dry place away from metal objects. If you plan on storing the battery for future use, store the battery at partial charge. Batteries are not intended to be stored for more than one year.
If you have multiple batteries for an application, rotate the batteries regularly. Remember that NiMH batteries will self discharge and should be deep cycled every 3 months.
Batteries prefer a shallow discharge . The number of cycles in a battery's life is dependent on type, use and depth of discharge per cycle. NiMH batteries typically have a life of 200-300 discharge cycles. Li-Ion batteries have a life of 500-1000 cycles.
Dirty battery contacts are the number one cause of charging problems. Clean contacts with rubbing alcohol and a cotton swab when needed.
Use the correct charger and charging procedure for the type of battery you're charging. Ni-cads (nickel cadmium) batteries require a different charging procedure from No-MH batteries, and both have a different procedure from Li-Ion batteries.
Ni-MH batteries get relatively hot when charging, but Li-Ion batteries should not. If a Li-Ion battery gets hot while charging, check the battery and the charger.
Charge the battery (regardless of type) for 8-12 hours on the first 3-5 charges.
Special Procedures for Ni-MH Batteries
For the first three charging cycles, be sure to charge the battery fully (overnight) and discharge it fully before charging. This properly conditions the battery and ensures it operates at its maximum capacity.
Ni-MH batteries need to be deep cycled every three months or 40 charge cycles to prevent a "memory effect" from developing.
There are no special procedures for Li-Ion batteries.