High-Performance BMS for Light Electric Vehicles
Background
Our client, a North American startup specializing in battery packs for the booming Light Electric Vehicle (LEV) market (e-bikes, e-scooters), was preparing to launch their flagship product. Their innovative battery design promised longer range and faster charging, but they needed a world-class BMS to ensure its safety and longevity.
The LEV market is fiercely competitive. The client was caught in a difficult position:
Local suppliers in North America quoted exorbitant prices for the design and manufacture of a high-reliability BMS, which would have made their final product uncompetitive.
Generic, off-the-shelf BMS solutions lacked the advanced features and safety protocols their design required.
They needed a partner who could provide a custom, cost-effective, high-reliability, ‘design-to-mass-production’ solution. They came to us seeking a specialist in complex power electronics who could help them scale from a promising startup to a market leader.
The Challenge: Safety Without Compromise
The client's engineering team faced a classic dilemma: balancing performance, safety, and cost.
Safety is Non-Negotiable
With thousands of their battery packs set to be on the streets, ensuring perfect cell balancing, temperature monitoring, and fault detection was their absolute top priority to prevent thermal runaway and fire hazards.
Complex Mixed-Signal Environment
The PCB had to safely manage a high-voltage 72V battery stack while simultaneously processing sensitive, low-voltage data for the microcontroller and CAN bus communication. Electrical noise and high-voltage isolation were major technical hurdles on a very compact board.
Intense Cost Pressure
To succeed in the LEV market, the final battery pack's Bill of Materials (BOM) was under extreme scrutiny. The BMS was a significant cost driver, and they needed to optimize it without taking any risks on safety.
The Vision: A Foundation for Growth
- Achieve best-in-class safety and reliability to build a trusted brand.
- Design a compact, integrated BMS that could fit within their custom, space-constrained battery enclosure.
- Find a long-term partner who understood their business and could scale with them from initial prototypes to high-volume production.
Our Solution: Engineering for Safety and Scale
- PCB Technology: A 6-layer FR-4 board with a high Comparative Tracking Index (CTI) of 600V to prevent surface arcing.
- Isolation Strategy: Physical separation with milled slots (cutouts) between high-voltage and low-voltage sections.
- Communication Bus: 120-ohm impedance-controlled differential pair routing for the CAN bus to ensure robust data integrity.
- Assembly: Full PCBA solution including sourcing of all components and application of a protective conformal coating.
Our Design & Development Process
Our process is built for speed, precision, and manufacturability, integrating every stage from initial concept to mass production. We don’t just follow steps; we embed expert engineering decisions into our workflow to solve our clients’ most difficult challenges.
- Safety-Driven Layout & Isolation: We engineer physical isolation using milled slots and strict adherence to IEC 60664 standards to guarantee high-voltage safety and prevent catastrophic failure.
- Flawless Communication Bus Design: By implementing 120-ohm impedance control and shielded routing, we ensure the CAN bus delivers error-free data, even in noisy electrical environments.
- Integrated Design for Assembly (DFA) Our designs are inherently optimized for our own SMT lines, which eliminates potential production issues, reduces your total cost, and ensures a smooth ramp-up to mass production.
- Accelerated Prototyping Cycle We deliver fully assembled prototypes in just 10 days. This allows your software and hardware development to proceed in parallel, dramatically accelerating your time-to-market.
Happy Clients!
How We Control Quality
Quality isn’t a checklist; it’s a culture. Our commitment is backed by:
- 100% AOI & ICT: Every assembled board is checked by Automated Optical Inspection (AOI) for visual defects and undergoes In-Circuit Testing (ICT) to verify every component is correctly placed and functional.
- Functional Testing: We implemented a custom functional testing jig, co-developed with the client, to simulate a real battery pack and test every feature of the BMS before it ships.
- Traceability: Full traceability of all critical components and production batches.
