====NiZn rechargeable (nickel zinc)====


===Positive characteristics===


•	Similar to NiCd but no toxic cadmium.


•	Zinc is less expensive than cadmium.


•	The nickel and zinc can be fully recycled.


•	Even lower internal resistance than NiCd.


•	Higher than normal voltage, nominal 1.6V per cell.


•	Can be recharged many times (500-600) if treated gently.


•	Fast recharge.

===Negative characteristics===

•	Reduced life (100-200 cycles) if heavily discharged - one manufacturer recommends using 80% discharge for longest life.


•	Moderate self discharge rate.


•	Careful handling required because of high current output - don't carry in your pocket, especially with a set of car keys.


•	Charging can be tricky - for 100% charge one manufacturer suggests using 2.5C for one hour, pause 5 minutes, then use constant voltage at 2.05V.


•	Actually first patented in 1901 but the tendency for the cathodes to break down due to dendrite formation have kept them off the shelves.