Software updates can influence the buffer settings in electric vehicle (EV) batteries by adjusting the usable range of the battery’s state of charge (SOC), which directly impacts battery longevity, performance, and usable capacity.
How Buffers Work in EV Batteries
- Battery buffers are safety margins set by the battery management system (BMS) to prevent the battery from charging fully to 100% or discharging down to 0%, both of which can accelerate battery degradation or even cause permanent damage (sometimes called “bricking”).
- The buffer comprises a top buffer (limiting maximum SOC) and a bottom buffer (limiting minimum SOC), creating a protected usable SOC window. This strategy helps slow aging by avoiding extreme voltage levels.
- These buffers are typically engineered based on the battery chemistry and type, as different cells tolerate charge extremes differently.
Influence of Software Updates on Buffers
- Software updates, particularly over-the-air (OTA), can modify the size of these buffers. For example, manufacturers like Tesla have the capability to adjust the buffer size through such updates to optimize battery health and longevity based on real-world data collected from many vehicles.
- Increasing buffer sizes reduces the usable energy capacity but protects the battery, slowing degradation. Conversely, decreasing buffer size can increase usable range but at a cost of potentially faster aging.
- These adjustments often come after manufacturers have gathered sufficient operational data about how a battery chemistry ages in service, allowing dynamic tuning of buffers to extend battery life.
- Some manufacturers also allow users to set custom charge limits via software updates, such as stopping charging at 75% SOC instead of 100%, which further improves longevity by increasing buffer margins on the top end.
Misconceptions and Practices
- Adjusting buffers is not used by manufacturers to “hide” battery degradation as it would require changing cell voltage limits, accelerating degradation rather than masking it.
- Instead, buffer recalibrations are deliberate, data-driven attempts to balance usable capacity and battery health.
- Software updates may also reduce available driving range temporarily if the buffer is increased to protect the battery at high mileage or after significant use.
Summary
Software updates influence EV battery buffer settings by recalibrating the battery management system’s limits on maximum and minimum state of charge. These changes optimize battery life and health by adjusting the usable SOC window, balancing performance with longevity. Over-the-air updates enable manufacturers to apply these optimizations dynamically, based on extensive operational data, and sometimes allow users to customize charge limits to better preserve battery life.
This approach explains why some EVs receive software updates that modify charging behavior and range without any physical battery change, reflecting how software actively manages battery buffers to protect the pack.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-do-software-updates-influence-the-buffer-settings-in-ev-batteries/
