Six keys to success in battery management system design
Batteries often take a back seat in project designs used in consumer and industrial applications.
Increasingly, lessons learned from the automotive industry translate neatly into these other uses and meet growing safety, security and longevity needs.
We recently met with Infineon’s Marcelo Williams Silva, senior product marketing manager for automotive and industrial, to discuss the latest trends in battery management system (BMS) solutions. Silva discussed lessons learned from battery design in the automotive industry that can successfully extend to industrial and consumer applications.
Whether you’re designing a forklift, a drone or an electric vehicle, pay attention to these six considerations to get your BMS design right from the start.
Taking all six of Silva’s points into consideration could solve most later design challenges.
Silva’s checklist for successful BMS design:
- Cell protection: Plan for tolerance in operating conditions.
- State of charge: Estimate capacity left in the battery, include range indicator.
- State of health: Estimate remaining useful lifetime of the battery.
- Cell balancing: Equalize charge on all the cells in the chain to increase longevity.
- Security: Design-in authentication and battery usage recording.
- Charge control: Consider options for charging optimization, interface to charger.
Let’s take a closer look.
BMS solutions are electronic control circuits that monitor and regulate charging and discharging of batteries. They monitor battery voltages, temperature, capacity, state of charge, power consumption, remaining operating time, charging cycles and other characteristics.
BMS designs ensure optimal use of the energy available in a battery. The systems protect batteries from deep discharge and over voltage. In the case of multicell batteries, BMS solutions also provide for cell balancing, which improves longevity.
The high-power density of lithium-ion batteries makes them popular, but their relatively unstable behavior requires they be handled with care. That’s why BMS solutions are needed to monitor battery states and ensure operational safety.
BMS design typically considers protection, the state of charge, useful life and cell balancing. Battery security, however, may be a new consideration for designers outside of the automotive industry.
Today’s BMS solutions enable designers to observe battery performance over time and deliver safer designs. This is essential in battery designs for human transportation or in healthcare applications where safety is critical.
Silva also offers four tips for competing successfully in the market. If you can design-in more autonomy and extend battery life, you’ll have a market advantage.
Win in the market by considering these points in your next BMS evaluation:
- Weight: If you can remove harness and reliability issues, do it.
- Energy density: Higher density means more power, and that requires improved safety.
- Aftermarket protection: Design for the long haul. One bad cell can potentially damage an entire system.
- High flexibility: Make sure your battery solution adapts to multiple products.
Jason Struble - Avnet transportation supplier manager at Avnet
Jason Struble has been with Avnet since 2011, working as a field applications engineer, technical sales engineer and most recently as a supplier manager in the transportation/automotive business unit. Struble’s experience in battery management, power supply, analog design, field application support and sales dates to 2005. Having both engineered and sold silicon devices, Jason enjoys introducing new electronics technology to the market by sharing practical experience.