BMS or Bust: Why Battery Management Systems Are Critical to the Industry

Since the advanced battery industry is growing adjacent to other large industries such as EVs and energy storage, batteries must be equipped to perform effectively under dynamic environments. The battery management system (BMS) is an important component of this goal, as it is critical to determining the lifespan of the battery. Guidehouse Insights believes that grid-facing energy management system software will be where the most innovation will occur in the advanced battery industry over the next several years, reaching $34.7 billion in 2025. Growth in the BMS industry will be similar.

What Is a BMS?

There is no clear definition of what constitutes a BMS, and the advanced battery industry has a fragmented interpretation as to what the system is supposed to do. Current standards do not adequately define BMS requirements; loopholes and conflicting literature exist across governing bodies. This has led to excessive supplier-driven standards developed from the bottom up rather than the top down.

A clear definition and list of attributes related to BMSs enable stakeholders to avoid confusion, add consistency across platforms, reduce complexity, increase safety, and reduce cost. Without a definition, the following can result:

• Inefficient cell and system designs
• Inconsistent requirements for cells, packs, and systems
• Costs inflation on the cell and pack levels
• Longer battery development timeline

Why Do We Need a BMS?

Voltage, current, and temperature are electrical constraints that are monitored from the outside of cells. This type of monitoring does not paint an accurate picture of the internal state and health of the batteries. Because of that, engineers tend to be conservative with how they design battery packs. Companies thus tend to be careful with how they market the use of the packs, and the full potential of the battery is rarely realized.

Guidehouse Insights believes outlining BMS requirements should be the first step to fabricating a universal standard. There is no one-size-fits-all solution; BMS regulation requirements should broadly fall into three categories:

• Electrical requirements: Voltage, current, system redundancy, state of health, and conversion interfaces
• Physical requirements: Packaging, thermal management, and mechanical interfaces
• Safety requirements: Cell and system, environmental, and end-of-life considerations

Companies are beginning to understand the importance of designing an effective BMS and are driving advanced battery researchers to push the limits of design and integrate into existing technologies. For example, Advanced Research Projects Agency-Energy (ARPA-E) awarded the University of Washington a $3.4 million grant to develop a BMS that uses internal advanced sensors to predict the physical state of the battery as a result of charging and discharging. This allows quick and accurate data to be used in decision-making surrounding how to control the battery to optimize its efficiency in real time.

Further, Imperial College London is working with its industrial partners to improve battery performance in EVs via a BMS. One project with Zap&Go, Codeplay Software, and PowerOasis aims to design an improved BMS that allows faster charging, enhanced power delivery, and longer vehicle battery lifespan.

Going forward, Guidehouse Insights believes that battery hardware and software manufacturers should continue to look to improve technologies surrounding the BMS and advanced sensors. The BMS is not just software used to maintain state-of-charge and/or monitor state of health. Rather, it is an amalgamation of components, functions, and features that are necessary to meet electrical, physical, and safety requirements. Improving these functions will stretch the lifespan and use cases of the battery system, increase safety, and grow profit margins for electrochemical batteries.