Principles of Power Battery Technology?
3 Answers
Battery Cell. A battery cell is the fundamental unit device that directly converts chemical energy into electrical energy, including electrodes, separators, electrolyte, casing, and terminals, and is designed to be rechargeable. Battery Module. A battery module combines more than one battery cell in series, parallel, or series-parallel configurations, with only one pair of positive and negative output terminals, and serves as a power source. Battery Unit. A battery unit is formed by connecting dozens of battery cells or battery modules in series, constituting a single battery unit. Several battery units connected in series form the power battery assembly.
The principle of power batteries essentially revolves around the movement of lithium ions within the battery to store and release energy. As I recall from my studies, in lithium-ion batteries, during charging, lithium ions move from the positive electrode material (such as lithium cobalt oxide) to the negative electrode material (such as graphite) for storage. During discharge, they flow back to the positive electrode, generating an electric current that drives the motor. This process relies on the electrolyte in between as a transport medium and a separator to prevent short circuits. The key advantage is the high energy density, which enables electric vehicles to travel longer distances, but thermal management is crucial because overheating can lead to safety issues. Engineers are still improving materials to enhance lifespan and charging speed—for example, ternary lithium batteries are more stable than traditional ones. In daily use, while fast charging is convenient, it accelerates aging, so I recommend following the manufacturer's guidelines for maintenance and avoiding excessive discharge. The key to prolonging battery health is maintaining steady usage habits, such as not letting the battery drain completely before recharging.
As a frequent electric vehicle user, I've gained practical insights into how traction batteries work during daily driving. Simply put, the battery converts chemical energy into electrical energy to power the motor. When charging, plugging in the charging cable causes lithium ions to move from one end of the battery to the other for storage. During driving, these ions flow in reverse to generate current that drives the wheels. It functions like an energy bank - convenient for storing and withdrawing electricity. However, it's crucial to avoid excessively low charge levels (I typically maintain above 20%) as this impacts battery lifespan. Lithium serves as the core element due to its lightweight and efficient properties, though cold winter temperatures reduce efficiency, which is why I always preheat my car in the garage. The driving range depends on battery capacity - my vehicle still maintains about 400 km after several years of use. For maintenance, regular slow charging better preserves battery health than fast charging, preventing overheating and deep discharge. Ultimately, understanding these principles gives me more confidence in driving without unexpected shutdowns.