Knowledge of the use and maintenance of lithium batteries

Lithium batteries are secondary batteries (rechargeable) that rely on lithium ions to move between the positive and negative electrodes. During charging and discharging, lithium ions are inserted and removed back and forth between the two electrodes: during charging, lithium ions are removed from the positive electrode and inserted into the negative electrode through the electrolyte. When unloading, the situation is just the opposite. Batteries generally use lithium-containing materials as electrodes, which is a representative of modern high-performance batteries. Lithium batteries are divided into lithium batteries and lithium batteries. Cell phones and laptops use lithium batteries, which are usually called lithium batteries, but lithium batteries are too dangerous to be used in everyday electronic products. Lithium ion, lithium battery: Lithium battery has the advantages of light weight, large capacity, no recall effect, etc., so it has been widely used. Now many digital devices choose lithium battery as the power source, although its price is relatively expensive. Lithium batteries have a high energy density, their capacity is 1.5 to 2 times that of a nickel-hydrogen battery of the same weight, and the self-discharge rate is very low. In addition, lithium batteries have almost no recall effect and no toxic substances, which is also an important reason for the widespread use of lithium batteries. Application and maintenance of lithium batteries: When using lithium batteries for charging lithium batteries, you should notice that the battery enters a dormant state after a period of time, and the current capacity is lower than the normal value, and the use time is also shortened. However, the activation of the lithium battery is very short. Only after 3-5 normal charge and discharge cycles can the battery be activated and the normal capacity can be restored. Lithium batteries have almost no recall effect due to their own characteristics. Therefore, do not use special methods or equipment to activate the new lithium battery in the user's mobile phone. When charging the lithium battery, a dedicated lithium battery charger should be used. Lithium battery charging adopts constant current/constant voltage mode. First, use constant current charging, and then use constant voltage charging when the battery is close to the terminal voltage. For example, a battery with a capacity of 800ma. h, where the final charging voltage is 4.2v. In the constant current charging of the 800 mA battery (charging rate 1c), the battery voltage initially has a larger slope. When the battery voltage is close to 4.2V, 4.2V constant voltage charging, the lithium battery current gradually decreases, the voltage changes little, and the charging current To 1/10c (approximately 80ma), the vicinity is fully charged, and the charging may be suspended (some chargers start a timer after 10c, and the charging is completed after a press of time). It is impossible to charge lithium batteries with nickel-cadmium rechargeable chargers (3 nickel-cadmium rechargeable batteries) (although the rated voltage is the same, they are all 3.6v). Due to the different charging methods, the battery is simply overcharged. (1) Charging voltage: the stop charging voltage related to the positive electrode material of the battery when the battery is overcharged. Coke is 4.1v, graphite is 4.2v. Generally called 4.1v lithium battery and 4.2v lithium battery. Please note that when charging, 4.1v batteries cannot be charged with 4.2v chargers, otherwise there is a danger of overcharging (4.1v and 4.2v chargers use different charger ICs). Lithium batteries have higher requirements for charging, and complex charging circuits are required to ensure the safety of charging. The accuracy tolerance of the stop charging voltage is ±1% of the rated value (such as ±0.042v for 4.2v lithium battery). Overvoltage charging can cause permanent damage to the lithium battery. (2) Charging current: The charging current of lithium batteries should be in accordance with the recommendations of the battery manufacturer, and a current-limiting circuit should be required to prevent the occurrence of overcurrent (overheating). The usual charging rate is 0.25~1C, and the recommended charging current is 0.5c (C is the battery capacity, such as a battery with a nominal capacity of 1500ma). h, charging current 0.5*1500u003d750mA). During high-current charging, the temperature of the battery is often tested to prevent overheating from damaging the battery or causing an explosion. (3) Charging temperature: When charging the battery, the ambient temperature must not exceed the temperature plan listed in the product characteristics table. The battery should be charged in the temperature range of 0~45℃, away from high temperature (above 60℃) and low temperature (-20℃) environment. 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: Analysis of the application field of lithium batteries