Marine energy storage supplier Sterling PBES has announced the completion of its most intense fire and safety testing to date.
The recent tests, the company said, validate the integrated liquid cooling, fire stop, and ventilation systems that come installed in its battery systems.
For the tests, a ferrous metal spike was driven through all plies of a cell in the battery, simulating catastrophic mechanical damage. Known as the most invasive and difficult test for a lithium battery, the nail penetration test simulates damage that may occur as a result of mishandling or impact from external forces.
Typically, in lithium-ion batteries, damage like this would result in a thermal chain reaction called thermal runaway where heat from the damaged cell causes the other cells in the battery to also ignite.
The release of the energy contained in the battery can result in temperatures of more than 800°C and the release of toxic and flammable gasses that are explosive when contained inside the hull of a vessel.
In the nail test, the damage inflicted upon the cell is compounded by the fact that the metal spike is conductive, creating a dead short to the internal circuits of the cell. In repeated tests, the damaged cell almost instantaneously reaches a temperature of over 500°C.
The company said that due to the integrated and robust cooling system, the heat did not affect adjacent cells. In fact, the adjacent cells did not reach more than 80° C, well within safe parameters. All gasses were safely released through the patented E-Vent ventilation system.