Battery Types
NiCD Batteries
Nickel Cadmium (NiCD) batteries are the oldest type of battery available. NiCD batteries weigh more than the other types but have the longest recharge cycle life if conditioned correctly (in plain language, they can be charged and discharged more times than any of the others without going bad). If NiCD batteries are not fully discharged before recharging, memory effect can build up, limiting the capacity of the battery to the point it was drained before recharging. So if you recharged it when only half empty on a regular basis, its capacity would be reduced to half in time. Because of memory buildup, NiCD batteries should not be used with cigarette lighter adapters unless fully discharged as car chargers do not discharge and condition the battery.
It is rare to find NiCD batteries still available for mobile devices due to their size and weight. Some camcorders and tools still use them but even in those settings they are becoming much more rare.
Pros –
Longest Charging Life
Cons-
Memory Effect
Size
Weight
NiMH Batteries
Nickel Metal Hydride (NiMH) batteries replaced NiCD batteries. NiMH batteries were smaller and lighter than NiCD batteries and do not have the “memory effect” issue. As a result NiMH batteries do not require conditioning and can be recharged regardless of current capacity.
Pros –
Small
Lightweight
No Memory Effect
Inexpensive compared to newest battery technologies
Cons-
Newer battery technology is smaller and lighter
Battery wears out in less charging cycles than NiCD
Lithium Ion Batteries
Lithium Ion (Li-Ion) batteries are lightweight and long lasting. Li-Ion batteries are light, slim, and provide the better talk time than NiCD or NiMH batteries. Li-Ion batteries have become the battery type of choice for most mobile devices currently.
Pros-
Small
Lightweight
No Memory Effect
Cons-
None, Best Current Technology
Lithium Polymer Batteries
Lithium Polymer (Li-Poly) batteries are the newest type of batteries. Li-Poly batteries are ultra light, slim, and provide the longest available talk time. Li-Poly batteries are available only for a limited number of phones and have not yet become popular.
Pros-
Light
Small
No Memory Effect
Cons-
Expensive