Summary Table of Nickel-based Batteries

Nickel-based batteries dwell between lead acid and Li-ion.

They are safe, economical and long-living but are increasingly being assigned to niche markets. Table 1 summarizes the characteristics of present, past and future nickel-based batteries.

Chemistry	Nickel-cadmium	Nickel-metal-hydride	Nickel-iron	Nickel-zinc	Nickel-hydrogen
Abbreviation	NiCd	NiMH	NiFe	NiZn	NiH
Type	Nickel cathode; cadmium anode	Nickel cathode; hydrogen-absorbing anode	Oxide-hydroxide cathode; iron anode with potassium hydroxide electrolyte	Similar to NiCd; uses alkaline electrolyte and nickel electrode	Nickel electrodes, hydrogen electrodes, in pressurized vessel
Nominal voltage	1.20V/cell (1.25)		1.20V	1.65V	1.25V
Charge	Taper charger. Constant current; floating voltage		Taper charger, similar to NiCd	Taper charger, similar to NiCd	Not defined
Full charge	Observing voltage drop; plateau voltage as override			1.9V	Not defined
Trickle charge	0.1C	0.05C	Not defined	No trickle charge	Not defined
Specific Energy	45–80Wh/kg	60–120Wh/kg	50Wh/kg	100Wh/kg	40–75Wh/kg
Charge rate	Can be above 1C	0.5–1C	Not defined	Regular charge	Not defined
Discharge rate	Can be above 1C	1C	Moderate	Relative high power	Not defined
Cycle life (full DoD)	1,000	300–500	20 years in UPS	200–300	Very long cycle life (>70,000 partial)
Maintenance	Full discharge every 3 months (memory)	Full discharge every 6 months	Not defined	Not defined	Maintenance free; low self-discharge
Failure modes	Memory reduces capacity, reversible	Memory (less affected than NiCd)	Overcharge causes dry-out	Short cycle life due to dendrite growth	Minimal corrosion
Packaging	A, AA, C, also in fractional sizes	A, AA, AAA, C, prismatic	Not defined	AA and others	Custom made; each cell costs >$1,000
Environment	Broad temperature range. Toxic	Considered non-toxic	Poor performance when cold	Good temperature range	Operates at –28°C to 54°C
History	1899, sealed version made commercial in 1947	Research started in 1967, commercial in the 1980s; derived from nickel-hydrogen	In 1901,Thomas Edison patented and promoted NiFe in lieu of lead acid; failed to catch on for ICE, EV	In 1901, Thomas Edison was awarded the U.S. patent for the NiZn battery	Problems with instabilities in 1967 caused a shift from NiMH to NiH
Applications	Main battery in aircraft (flooded), wide temperature range	Hybrid cars, consumer, UPS	German V-1 flying bombs, V-2 rockets; railroad signaling, UPS, mining	Renewed interest to commercial market with Improvements	Exclusively satellites; too expensive for terrestrial use
Comments	Robust, forgiving, high maintenance. Only battery that can be ultrafast charged with little stress	More delicate than NiCd; has higher capacity; less maintenance	In 1990, Cd was substituted with Fe to save money. High self-discharge and high fabrication costs	High power, good temperature range, low cost but high self-discharge and short service life	Uses a steel canister to store hydrogen at 8,270kPa (1,200psi)

Table 1: Summary of most common nickel-based batteries.

Experimental and less common versions are not listed. All readings are estimated average at time of publication. Detailed information is on BU-203: Nickel-based Batteries.