Smart batteries, also known as Smart Battery Systems (SBS), it’s a branch and an important part of modern power technology. Smart batteries use internal electronic circuits to measure, calculate and store battery data, it makes the use and management of power more predictable. The basic functions of the battery management system are divided into detection, management, protection three parts.Specifically, including data acquisition, status monitoring, balance control, thermal management, security, information management and other functions.

Battery parameter acquisition

Battery parameter acquisition mainly includes the battery pack in the battery voltage, the system current, the system temperature acquisition, the parameters can be used to determine the battery remaining power, fault protection. Voltage of Lithium-ion battery can best reflect the performance of the battery, both for overcharge, over discharge and other fault protection, can also be used to initially estimate the remaining power of lithium-ion battery. System current can be used to determine whether there is over-discharge or over-current, but also through integration current and time, estimate the remaining battery power. System temperature is mainly used to prevent the battery temperature higher, occur security incidents, and compensate for the remaining capacity calculation. The remaining power is an important parameter to reflect the performance of the battery，it’s also the basis judgment for main engine of charge, discharge. Accurate estimation of the remaining power can protect the battery, to prevent overcharge, over discharge occurs, to facilitate customers to make a reasonable time schedule.

Battery pack fault protection

When using a lithium-ion battery, you must provide battery pack failure protection, overheating or overcharge, which may cause fire or explosion. Smart battery management system can be divided into primary protection and secondary protection. Primary protection detects the current, voltage and temperature and the remaining power of battery pack, to determine whether the battery pack overcharge, over discharge, over temperature, overcurrent and short circuit and other unsafe state and shut down the battery pack in time, to avoid damage to the battery pack. Secondary protection can provide backup protection in the case of primary protection failure, fuse fuse, permanently shut down the battery pack, to prevent the battery in the unsafe conditions continue to charge and discharge.

Fuse the fuse, shut down the battery pack permanently, to prevent the battery in the unsafe conditions continue to charge and discharge.

Cell balance

As the lithium-ion battery production process restrictions,, as well as the influences

For the battery of temperature, discharge rate during use, there are differences in voltage, internal resistance and capacity between the individual cells in the battery pack, and after several cycles, the difference will become more obvious, resulting  the average cycle life is more shorter than single cell. At the same time for lithium-ion batteries, because of its high charge and discharge requirements, when overcharge, over discharge, overcurrent and short circuit, etc.,  The heat of lithium battery is increased significantly, prone to spark, burning or even explosion. To ensure safety and stability, balanced measures must be taken.

SMBus communication

The system management bus, (SMBus) is a two-wire interface. Through it, between the equipment and the equipment and other parts of the system can communicate with each other. It is based on I2C operating principle. SMBus provides a control bus for system and power management-related tasks. A system uses SMBus to communicate information with multiple devices without the need for independent control lines. The intelligent management system needs to provide SMBus communication function to facilitate the main engine to read the conversion data and status information, and control the intelligent battery management system according to the requirement of main engine.