NiMH Batteries - A quick look

NiMH rechargeable batteries are rechargeable versions of NiMH batteries. They consist of nickel oxy-hydroxide anode and a hydrogen absorbent cathode. NiMH rechargeable batteries measure 1.35 to 1.4 volts when fully charged and 1.2 volts during discharge. It is advisable to use a battery charger for charging rechargeable NiMH batteries.

There are various methods employed for charging NiMH rechargeable batteries. Some of them are listed below:

Trickle charging:  trickle charging is normal low-current charging with or without the presence of a timer. Since NiMH batteries suffer from a disadvantage namely release of hydrogen gas on excess charging, a timer is recommended.

Manual charging: NiMH rechargeable batteries can be charged on constant-current or constant-voltage but it would be better if the voltage and current values are set previously or a timer is used to prevent overcharging.

Voltage drop charging: this method works on the principle of constant current where the charger reverses the voltage polarity of the battery as it begins to overcharge. Thus, there is a voltage drop in the battery terminals and the charger immediately stops the charge cycle.

Temperature charging: this method is based on the principle of law of conservation. It provides constant voltage to the battery and when the battery is not in use, the whole charge is being converted into chemical energy. If overcharged, this stored chemical energy will be dissipated in the form of heat, thereby causing the battery temperature to increase. Thus, a temperature sensor is attached to these rechargeable batteries.

No related posts.

Related posts brought to you by Yet Another Related Posts Plugin.