14250 battery

　　Breakthrough in high-power 14250 battery protection technology, manufacturers rush to enter

　　With the advancement of technology and the increasing requirements for environmental protection, lithium batteries are gradually becoming the mainstream of rechargeable batteries, especially in the field of mobile electronic products. Lithium batteries rely on high energy density and have occupied almost all markets. However, in some application fields with relatively high power requirements, lithium batteries still have a low share because they do not have advantages in terms of cost and discharge rate indicators. For example, in the field of electric bicycles, lead-acid batteries still occupy a high share. In the Chinese market, lithium batteries only account for about 1% of the market share, while in developed countries in Europe and the United States, they account for about 50%. The main reason for such a low market share is of course price, but the service life and safety of lithium batteries themselves are also major shortcomings. If these problems cannot be solved well, they will greatly affect the market share of lithium batteries.

　　To solve the problem of the life and safety of lithium batteries, special monitoring and protection circuits are needed. This is a characteristic of lithium batteries compared with other batteries. It must have a protection circuit, otherwise it will explode due to heat. There have been copycats in the past. Mobile phones use lithium batteries without protection circuits, and there are reports of injuries caused by battery explosions. From this we can see the importance of protection circuits. In the past, many protection circuits were built with discrete components, which had no advantages in terms of cost and reliability. In response to this market situation, Texas Instruments launched the industry's first power supply oriented Tools with the bq77910, a single-chip battery management device for electric bicycles.

　　Why it is used for power tools and electric bicycles? This starts with the number of battery strings supported. Because the support range of this device is 4 to 10 strings, it can support up to 20 strings of batteries through cascading. The number of strings of lithium batteries determines its output voltage. 10 strings means the output voltage is 34V. Within this range, the battery's The application scope is electric bicycles, electric scooters, portable gardening tools, power tools and uninterruptible power supplies (UPS), etc. There are certain requirements for voltage and current requirements, but the requirements are not very high. If you want to enter the field of electric vehicles, then the number of strings can reach more than 100 strings, which is not an area that this device can cover.

　　The main function of the battery protection circuit is to maintain the safe operation of the battery pack under various conditions, extend the service life of the battery as much as possible, and ensure full charging and utilization of the battery pack without exceeding the safety threshold. bq77910 is an integrated battery management solution that provides all necessary battery pack protection functions and integrated power balancing functions, including: battery cell overvoltage, battery cell undervoltage, charging short circuit, discharge short circuit overcurrent, battery pack temperature, Open-circuit and short-circuit thermistor detection and open-circuit battery unit detection, power-down protection, and other functions to prevent power FET from overheating. Its biggest feature is that it operates as an independent device without the need for an external microprocessor, and the logic control part is integrated internally, which makes the overall solution low-cost possible.

　　The high-power battery pack targeted by this device faces great challenges in application, such as extremely high current, which requires large discharge current, small charging current, and the load itself must be separated from the battery. Separate charge and discharge paths are also required so that appropriate protection path components (MOSFETs) can be selected according to the required size, thereby reducing costs. In some application fields, such as electric vehicles and UPS, rapid charge and discharge conversion is also required. These have brought great technical challenges to the design of battery packs and protection circuits.

Read recommendations:

Coin Battery CR 1216

What changes will water cause in lithium-ion batteries?

Characteristics of lithium battery separator

3.2v 320ah lifepo4 battery

902030 polymer battery