TI’s wireless BMS consists of the CC2662R-Q1 wireless MCU and the BQ79616-Q1 16-channel automotive battery monitor, balancer and protector. The main pillar of the system however is probably Texas Instruments’ proprietary software protocol running on this MCU – the company claims that this is the industry’s highest-performing solution for wireless BMS.
Wireless BMS, in general, have the big advantage that they help developers to reduce the cabling complexity. By reducing complex cabling, the batteries also lose weight and become cheaper – a significant benefit in today’s EVs at the verge of entering cost-sensitive mass market. In addition, the systems gain reliability and robustness. At least according to the argumentation of the providers, such systems are less susceptible to failure. While the theoretical possibility of RF-induced interference comes into play with wireless systems, TI says it has taken this issue into account by developing a highly secure radio protocol that includes features such as AES-128 data encryption, key exchange and refreshment, message integrity checks and a unique device authentication.
This deterministic protocol provides the highest throughput in the market claims TI. Thus, it enables automakers to create a battery module using a single wireless system-on-chip connected with multiple BQ79616-Q1 battery monitors for different configurations such as 32-, 48- and 60-cell systems. The system is designed to support up to 100 nodes with a very low latency of less than 2 ms per node and time-synchronized measurements across every node. The CC2662R-Q1 wireless MCU isolates individual cell monitoring units, eliminating the need for and cost of daisy-chain isolation components.
On behalf of TI, TÜV SÜD as functional safety certifcation agency has evaluated the quantitative and qualitative error-detection performance of this wireless BMS functional safety concept, as well as the feasibility for automakers to achieve Automotive Safety Integrity Level (ASIL) D, the highest level of International Organization for Standardization (ISO) 26262 certification.
Neutral observers are also convinced of the advantages of wireless BMSs. “The implementation of such systems will be a growing trend in the EV marketplace because these advancements provide greater flexibility of design while also lowering the complexity and cost relative to traditional systems,” said Asif Anwar, director of the powertrain, body, chassis and safety service at Strategy Analytics. “By demonstrating a solution that combines these advantages with ASIL D compliance, the TI solution sets a benchmark for the industry to follow.”