What are the disadvantages of Ni-MH batteries?

1. High self-discharge rate: 30~35% of self-discharge rate is stored at room temperature and fully charged 2. High temperature function is poor 3. Working principle of nickel-hydrogen battery is an important component of overcharge and discharge gas discharge. The anode of nickel-hydrogen battery Nickel hydroxide (OH) 2, an important component of the negative electrode is the pollution-free material hydrogen storage alloy powder (M) and potassium hydroxide in the electrolyte aqueous solution. In the planning of Ni-MH batteries, the capacity is actually surplus from positive and negative capacity planning to ensure that when overcharging, the oxygen from the positive electrode can respond to the negative electrode, and the internal pressure of the battery will not increase significantly. The charging method of the Ni-MH rechargeable battery is to restore the original rechargeable battery capacity. In order to make the battery reach the long-term use intention, it must be charged by an appropriate charging method. The better way is-its V value controls the charging, in addition to other controls Choice of approach. 1. It should be charged at an ambient temperature of 10~30℃, at which time the charging power is the best. When the ambient temperature is lower than 0°C, the gas absorption response inside the battery is insufficient, which causes the internal pressure of the battery to increase, activates the safety valve, and causes the battery to leak and deteriorate the function. When the ambient temperature is higher than 40°C, the charging power drops. This may cause deterioration of battery function and leakage. 2.-△V value: 5-10mv/piece. During the charging process, suppose the voltage drops from the peak value of 5 to 10mV, and then intermittently charging, and the charging becomes a trickle. 3. DT/DT value: 0.8~1℃/min. Use a thermistor or temperature sensor to detect the battery temperature. 4. TCO: The maximum charging temperature of d-type, f-type, 2/3m, m-type batteries is 48℃, and other batteries are 50℃. It is assumed that overheating of the battery during charging will affect functions such as battery life. The V detection line must emit charge at the initial moment, but it can emit at dT/dT at this time. 5. Initial delay: 10 minutes, prevent the deltaV detection line from starting within one press time after initial charging. Since the Ni-MH battery is left for too long or the voltage will oscillate after charging (false-triangular V), the delay is now set to prevent false-triangular V from triggering the charging interruption. 6. Trickling charging current: 1/30~1/20c. If the trickle charging current is too large, the battery temperature will increase and the battery function will be reduced. 7. Total charging time: 10-20 hours (depending on the size of the charging current). Even drip-type charging, prolonged overcharging can cause degradation of battery function. 8. Resolutely prevent reverse charging. Reverse charging will cause the internal pressure of the battery to rise, the safety valve is activated, the battery leaks, the function is degraded, and the battery may even break. 9. Do not charge the battery counter electrode, and do not overcharge the battery with high current, otherwise gas will quickly occur, causing the internal pressure of the battery to increase, and the battery swells or breaks. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: 18650 lithium battery application field