For users, a high-quality car jump starter is not only capable of a successful jump start, but also durable enough for years of use with a single purchase—that is what defines an excellent car emergency jump starter. So how can we make a car emergency jump starter both easy to use and long-lasting? This is where the BMS (Battery Management System) comes into play.

The core algorithms of BMS can accurately estimate the State of Charge (SOC) and State of Health (SOH) of the battery, and resolve the inconsistency of the battery pack through balancing technology.

For users, it is crucial to know the "remaining power" and "battery health" of the jump starter—and this is exactly where BMS’s state estimation function excels. BMS uses sophisticated algorithms such as the Ampere-Hour Integration method and Kalman Filter to accurately calculate the battery’s SOC and SOH. The Ampere-Hour Integration method measures SOC by accumulating the electric charge entering and exiting the battery, while the Kalman Filter dynamically corrects measurement errors to improve estimation accuracy. High-end BMS can achieve an SOC estimation precision of 5%.

Balancing management is another key technology of BMS. Due to differences in manufacturing processes and operating environments, inconsistencies in voltage and capacity are inevitable among individual cells in a battery pack. BMS uses active or passive balancing technology to transfer energy from cells with higher voltage to those with lower voltage—much like pouring water from a fuller cup into a less full one to equalize their levels—ensuring the synchronized performance of the entire battery pack. Passive balancing discharges high-voltage cells via shunt resistors, while active balancing transfers energy using inductors or DC-DC converters with higher efficiency. This aligns all cells in the battery pack to "march in step", effectively preventing premature failure of some cells caused by overwork and thus extending the cycle life of the entire battery pack.