UL code adds non-cascading requirement

In order for the in-building, lithium ion grid storage market to scale, it is clear that the safety of such systems will need to be thoroughly understood and addressed.

A significant step in that direction was the recent addition of Section 37, Internal Fire Exposure Test, in the updated UL 1973 certification standard this month.  This new section directly requires the prevention of internal thermal cascading such that the failure of one internal cell does not result in the propagation of fire to other cells which in turn could result in an explosion.   Going forward, every ESS in the market that seeks to be certified under UL 1973 or its successor, UL 9540, will need to comply with this requirement.

Safety is critical and at the heart of our technology, and safety considerations along with cost and performance metrics are inherent in every cell that is produced under our design.

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