====NiMH rechargeable (nickel metal hydride)====

===Positive characteristics===
•	Can give very high current output.


•	Not much capacity loss under heavy loads (little to no Peukert Effect).


•	Very level output voltage.


•	Can be recharged many times (500+) if good quality and treated well.
•	Little voltage depression ("memory" effect).


•	No cadmium (more environmentally friendly than NiCd).


•	Roughly 150% the gravimetric storage density (by weight) or up to 220% the volumetric storage density of NiCd.


•	Can be stored in any state of charge.


===Negative characteristics===

•	Must not be over discharged (and prefers shallow discharges).


•	Moderately high self discharge (30% per month), although Sanyo Eneloop claims to hold a 90% charge over 6 months and 85% over 12 months.


•	Need special chargers because overcharging can damage the battery - this means an ordinary NiCd charger may damage your NiMH battery.