Heated Ski Uniforms

Background

In 2008, a start-up company in Northern Europe — where skiing is a national passion — set out to launch an innovative heated ski uniform designed for use in harsh alpine environments. Operating at high altitudes and extremely low temperatures (down to -20°C), the product’s reliability depended heavily on the performance of its battery pack.

During early field testing, the customer identified a critical issue:

The State of Charge (SOC) display became inaccurate in sub-zero temperatures.

Heating functionality could shut off unexpectedly.

Users could not rely on the remaining usage time displayed.

This compromised both the functionality of the uniform and the overall user experience.

 

Key Challenges

Cold climate performance – ensure stable operation at temperatures as low as -20°C.

Accurate SOC display – provide reliable runtime information to users in extreme conditions.

Comfort and portability – battery must remain lightweight and seamlessly integrated into the ski uniform.

Time-to-market pressure – as a start-up, the customer needed a rapid solution to secure early market entry.

 

Our Solution

Our engineering team developed a tailored battery solution (2S 7.2V 18650 battery pcak and li-polymer battery pack) addressing these unique requirements:

Low-temperature optimized BMS with advanced voltage compensation algorithms for precise SOC calculation.

NTC thermistor integration enabling real-time temperature monitoring.

Preheating logic and insulation materials to improve discharge efficiency under sub-zero conditions.

Temperature-adaptive SOC estimation algorithms to ensure accuracy regardless of environmental fluctuations.

 

Results

Stable operation: battery pack performed reliably even at -20°C.

Accurate SOC display: users could trust the runtime indication, improving confidence and comfort.

Enhanced user experience: consistent heating performance increased satisfaction among skiers.

Market success: the start-up’s product launch was well received, enabling the brand to establish a strong presence in the Northern European ski gear market.

 

Next Steps

Following the success of this project, we are collaborating with the customer on the next generation of heated apparel battery systems, focusing on extended runtime and further weight reduction.