What are the charging methods for lithium batteries?

What are the charging methods for lithium batteries? The charging methods for lithium batteries vary depending on the number of batteries, battery structure, and power source type. At present, there are three main ways to charge lithium batteries: linear charging, Buck charging and SEPIC charging. The specific operation is as follows: Tatu lithium battery 1. Linear charging method of lithium battery When the input voltage of the charger is greater than the open circuit voltage of the fully charged battery and sufficient no-load point, it is best to use the linear method, especially the 1.0c fast charging current is not When it is too large than 1A. Portable devices, such as smart phones, PDAs, portable multimedia players, digital cameras, digital cameras, GPS navigation devices and USBMAX8677A can work independently with AC adapter power input, or at any two input input: when connected to an external power supply, The intelligent power selector allows the system to be connected to the battery or the battery is deeply discharged without connection. The intelligent power selector automatically switches the battery to the system load, uses the unused input power part of the system to charge the battery, and makes full use of the limited USB and adapter input power. All required current detection circuits, including integrated power switches, are integrated on the chip. The DC input current limit can be adjusted to 2A, and both DC and USB inputs support 100mA, 500mA and USBhang modes. The charging current can be adjusted to 1.5a, which supports a wide range of battery capacity. Other features of the MAX8677A include thermal regulation, overvoltage protection, charging status and fault handling, good power supply monitoring, battery thermistor monitoring, and charging timer. The MAX8677A is available in a space-saving, temperature-increasing, 4mmx4mm, 24-pin TQFN package, and can work in an extended temperature range of -40 to +85°C. 2. Lithium battery step-down switch charging method When the 1.0c charging current is greater than 1A, or when the input voltage is much higher than the battery's full open voltage, Buck or Buck is the better choice. For example, in a hard disk-based PMP, a single-cell lithium battery is usually used, with a fully charged open circuit voltage of 4.2v, and a capacity ranging from 1200 mA to 2400 mA. At present, PMP generally uses on-board charging, and the output voltage range is 9V~16V. The high voltage difference (minimum 4.8v) between the input voltage and the lithium battery voltage reduces the efficiency of the linear approach. This low efficiency, coupled with a 1C fast charging current greater than 1.2a, may cause serious cooling problems. In order to prevent this situation, the Buck method 3. SEPIC (boost and buck) switch charging method of lithium batteries is used. In some devices that use three or even four lithium-ion/polymer batteries, the input voltage of the charger is not Not always greater than the battery voltage. For example, a laptop computer uses a 3-cell lithium battery pack with a full open circuit voltage of 12.6v (4.2v×3) and a capacity of 1800 mA to 3600 mA. The input power supply can be an AC/DC adapter with an output voltage of 16V, or a carkit with an output voltage of 9V to 16V. Obviously, neither linear nor buck can charge the battery. This is achieved through the SEPIC method, which can work when the output voltage is higher than the battery voltage, or when the output voltage is lower than the battery voltage. 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: How to improve the safety of polymer lithium batteries?