Nickle Zinc batteries
Useful infomation
NiZn do profit of higher nominal voltage, which can make easier in some devices, to replace alkalines or any other 1,5 V primary cells. For instance I have buzzer with LCD, whose contrast is very low at 1,2 V provided by NiMH cells, making it almost illegible. They are also able to provide high current, what is good for devices like cameras, battery drills or toys.
However those cells also have a lot of cons. At first they have shorter live span, roughly cca. 200 cycles (caused by dendrite growth of Zn electrode, which perforates separator and will short out internally cell). Higher nominal voltage of freshly charged cell (up to 1,9 V) can also fry some devices without input voltage regulation. For instance my Casio calculator manual warns about using AAA Oxyride (NiO(OH)) cells, which have 1,7 V nominal voltage, so NiZn I could not put here also. Another problem is self discharge, they tend to selfdischarge as fast as NiCd, or even faster after more charge cycles, so they are not good as backup source of power like LSD NiMH. At last, charging NiZn requires different type of charger, because NiZn uses CCCV charge method instead of CC with deltaV peak control used by NiCd\NiMH, so yeah, you have to buy another charge for NiZn cells or use ensure, that you are using CCCV charging method, if charging with laboratory DC power supply.
Pro x contra table
Pro
Contra
NiZn do profit of higher nominal voltage, which can make easier in some devices, to replace alkalines or any other 1,5 V primary cells. For instance I have buzzer with LCD, whose contrast is very low at 1,2 V provided by NiMH cells, making it almost illegible. They are also able to provide high current, what is good for devices like cameras, battery drills or toys.
However those cells also have a lot of cons. At first they have shorter live span, roughly cca. 200 cycles (caused by dendrite growth of Zn electrode, which perforates separator and will short out internally cell). Higher nominal voltage of freshly charged cell (up to 1,9 V) can also fry some devices without input voltage regulation. For instance my Casio calculator manual warns about using AAA Oxyride (NiO(OH)) cells, which have 1,7 V nominal voltage, so NiZn I could not put here also. Another problem is self discharge, they tend to selfdischarge as fast as NiCd, or even faster after more charge cycles, so they are not good as backup source of power like LSD NiMH. At last, charging NiZn requires different type of charger, because NiZn uses CCCV charge method instead of CC with deltaV peak control used by NiCd\NiMH, so yeah, you have to buy another charge for NiZn cells or use ensure, that you are using CCCV charging method, if charging with laboratory DC power supply.
Pro x contra table
Pro
- High nominal voltage
- Can be used well in high drain devices
- Well recycleable
- Zn is widespread metal
Contra
- Lower capacity : volume or capacity : weight ratio
- Shorter live span
- High voltage can damage some devices
- NiMH chargers cannot be used with NiZn cells
- Moderate high selfdischarge