Fast, high-precision battery management system extends battery life and mileage

More and more car manufacturers are beginning to reflect on and rethink the way cars are powered. There are many reasons to drive this change, from concerns about fuel dependence to a desire for clean air to regulatory regimes. Industry experts say that by 2025, 25% of the cars sold will be equipped with electric engines.

Electric, hybrid, and plug-in hybrid vehicles rely on large lithium-ion battery packs consisting of hundreds or even thousands of independent primary batteries. To ensure safe, efficient and long-lasting operation, precise management of these primary batteries is essential. The voltage between the primary cells must be monitored and balanced, and the battery temperature must be monitored to help extend battery life (making it comparable to the life of the car) and the mileage of the car.

A fast, high-precision battery management system meets these requirements. Regarding the battery management system, you can choose different types of architecture. The Isolated Controller Area Network (CAN) architecture is based on a star configuration and is very reliable. A breakpoint on the communication line affects only one IC, while the rest of the battery pack remains safe. But the CAN architecture does have a high bill of materials (BOM) cost, and each IC requires a microcontroller and CAN, and the communication speed is relatively slow. Another option is the daisy chain architecture, which is recognized in the industry as providing reliable communication at a faster rate than the isolated CAN architecture, and at a much lower cost.

Fast, high-precision battery management system helps extend the mileage of electric vehicles

Highest safety level solution to meet ISO26262 and ASIL D requirements

Maxim's battery management system is the result of deep system knowledge and extensive IP portfolios that have been stored for decades, meeting ASIL D safety requirements. These systems enable fast, high-accuracy measurements with their proprietary daisy-chain architecture and fast SAR ADC. These battery management systems are also ideal for multi-noise automotive environments, providing high EMC immunity.

The MAX17843 is a 12-channel, high-voltage, intelligent sensor data acquisition interface and is one of Maxim's latest battery management ICs. With differential UART communication, this reliable battery management system IC provides trusted communications for both centralized and distributed architectures. The MAX17843 supports both capacitor and transformer isolation, so you can choose to use a capacitor instead of a higher cost transformer. This approach saves up to 90% of the isolated BOM cost while also reducing the failure rate (FIT).

Maxim's latest battery management technology, including the MAX17843, has the industry's only single-chip solution that meets the ASIL D standard. To be sure, some OEMs only require compliance with the ASIL C standard. However, having an ASIL D compliant IC makes it easier to implement the ASIL C solution. The FIT rate of the MAX17843 is less than 1. ASIL C requires a system FIT rate below 100. Given that there may be eight or more such ICs in an electric car's system, you will see that ICs with lower FIT rates are more likely to guarantee a system's FIT rate below 100. The MAX17843 also meets the requirements of the ISO 26262 standard, and its design and management process also meets TUV certification.