As a low-cost, convenient and green travel tool for short-distance travel, electric vehicles have also become the first choice of residents for short-distance travel. According to data, the average daily demand for bicycle rides exceeds 200 million times, while the average daily demand for two-wheeled electric vehicles reaches 700 million times, and the market demand

Lithium batteries are widely used, ranging from civilian digital and communication products to industrial equipment to special equipment, etc. They are all used in batches. Different products require different voltages and capacities. Therefore, lithium-ion batteries are used in series and parallel in many cases. The application battery formed by adding a protection circuit, casing and