Battery management system development for zero-emission tankless water heaters
About the client
Luthmore, a UK-based company, is revolutionizing the residential heating sector with its tankless water heating solution. Their technology offers a more sustainable way to provide hot water to households.
The challenge
Luthmore was looking to ensure instant hot water supply that would work steadily. For this, they needed to introduce a high-capacity battery into their solution. However, to ensure optimal battery performance and safety, the client needed expert assistance to develop a battery management system (BMS) for the system.
Delivered value
Solution
Lemberg Solutions delivered the BMS software before the deadline to ensure the client can test and launch their instant hot water supply system to the market as soon as possible.
First, we divided the software development process into two core milestones:
- Temperature and voltage readings functionality development; implementing controlled battery charge and discharge processes.
- Diagnostics functionality and system performance optimization.
As a result of the first milestone, we engineered software for a battery management system that ensures optimal battery performance with the following features:
- Cell voltage level monitoring and pack output current management.
- Battery temperature control at multiple points.
- A cell balancing feature ensuring equal voltage distribution across the batteries, with charger disconnection if balancing is ineffective.
- An automated load disconnection function using DC contactors to prevent any hazardous situations.
While we completed the software development for BMS, the charging and system controllers, which were critical for testing, were still being developed. To keep progress on track, we implemented software emulators that replicate the behavior of missing systems to test the solution and validate the functionality of the system.
After the initial samples of the BMS boards were delivered to Lemberg Solutions, our engineers performed a board bring-up and tested all the board functionality.
During the testing phase, the client pinpointed the areas they wanted to change, which we addressed in the second milestone. The focus was on expanding the diagnostic functions of BMS and optimizing system performance. To achieve this, our experts:
- Set up a cooling pump using pulse-width modulation to regulate the temperature and reduce the noise produced by the device.
- Adjusted cell balancing limits and implemented multistage fault detection to efficiently address different types of faults.
- Implemented a watchdog timer to monitor and ensure that multiple chips operate correctly.
After making all the necessary improvements, we completed the project. Now our client is preparing to launch the product on the market.
It was refreshing to work with a partner who added value and was able to turn system-level requirements into iterative and testable working software. The team proved to be flexible and took ownership of hurdles that needed to be overcome, even if they were unexpected. Lemberg showed excellent attention to detail during the quote phase and progress reviews, which made delivery smooth and on schedule. Communication was extremely collaborative and it felt like having an extension of our team.
How it works
