Comparison and analysis of lithium batteries and nickel-metal hydride batteries

Comparison of the range of use The comparison between lithium batteries and nickel-metal hydride batteries is that lithium batteries are more suitable for use on products with low current (such as mobile phones), but if they are used on products with high current (such as digital cameras), due to the current The demand is greater, and the power consumption is much larger than that of mobile phones. Lithium batteries are in short supply. Therefore, nickel-metal hydride batteries with large current, large capacity, high energy density and large power output will be better used. Comparison of advantages and disadvantages. Advantages of lithium batteries: There is no memory effect (referring to the phenomenon that if the battery is a nickel-cadmium battery, it is easy to leave traces in the battery and reduce the battery capacity if it is not charged or discharged for a long time. Another explanation says Yes: The battery is like memorizing the user's daily charging and discharging range and mode. It will be difficult to change this mode over time, and large-scale charging or discharging can no longer be done.), light weight. Disadvantages: high cost, low current, intolerant of over-full charge (compared with nickel-hydrogen battery). Advantages of Ni-MH battery: low price, strong versatility, large current, environmental protection, no pollution, and good stability. Defects: heavy weight and short battery life. Comparison of charging modes The design of the Ni-MH battery charger and the lithium battery charger is based on the voltage in principle, and the charging method for the design with or without the memory effect is also different. In terms of voltage, the end-of-charge voltage of Ni-MH battery chargers is generally set to 1.4V, and some chargers can also extend upward or downward a bit. Depending on the condition of the battery, if the battery is discharged below 1.1V, it may not be charged. , The highest 1.4V is the upper limit that cannot be broken under normal circumstances. For Ni-MH batteries, discharging at 1.1V is of little significance, because the capacity cannot be supplemented during charging. Lithium battery chargers are generally one-to-one processing, that is to say, a single-cell lithium battery is designed with a rated voltage of 3.6V~3.7V and a charge termination voltage of 4.1V~4.2V. Different series and parallel situations, lithium battery pack design The voltages are not very similar. In use, due to the different internal structures of lithium batteries and nickel-metal hydride batteries, the constituent materials of lithium batteries are active materials, so there is no memory effect, so avoid overcharging. The nickel-hydrogen battery is different. After a long period of time, the electrolyte will crystallize to prevent the charger from overflowing with electricity. This is where the memory effect begins to take place. The correct way is to activate. There are two types of activation. One is full charge and discharge without capacity loss, and the second is after capacity loss occurs. If the capacity loss is more than 1/10, this is almost unusable. At this time, 1.5 times the charging time can be used to activate the already crystallized substances inside, thereby restarting the nickel-metal hydride battery. Correspondingly, the charging process is accompanied by an increase in voltage. The termination voltage of the nickel-metal hydride battery charger is designed to be 1.4V. The conditions are prepared for this 1.5 times the duration of charging. At present, some chargers also provide a charging protection method, which will adjust the charging mode according to whether the battery power is overflowing or not, which can effectively protect the battery. Lithium batteries can be charged at any time and have little impact on life. For batteries with fuel gauges such as PPCs, it is recommended to charge them after they are dead. Beware of the impact. It can be charged at any time and can be disconnected at any time. If the battery is fully charged and continuously charged, it will affect the battery life. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: Power lithium ion battery will soon exceed the cost threshold of US$100/kWh