The US Sandia National Laboratories has introduced a crush test to their portfolio of ways to ‘kill a battery’, with a system that drops a 200+ pound weight onto lithium-ion cells.
The testing method, which hits with enough force to smash a battery in half, is thought to be the first of its kind in the US and will inform manufacturers on how to make batteries safer for electric vehicle applications.
Sandia mechanical engineer June Stanley (pictured right with fellow engineer Chris Grosso) said data collected from the tests would also help inform emergency responders attending incidents such as electric-vehicle crashes.
The crush test is one of nine methods available to the researchers as they investigate how batteries respond to stress.
Stanley said: “As far as we know nobody in the US has done any drop tests for impact testing like this; this is more real world, more realistic to what would happen.”
“The test can give us a better understanding for first responders and how they handle an emergency. It can also be beneficial for industry researching and developing new technology.”
In the tests, batteries sit at the base of a drop tower, which is housed in a vented, hangar-type building. The batteries sit in a steel tray, bolted to a load cell to measure the impact force at the base of the tower when a weight of at least 200 pounds is dropped from a height of up to 8 feet, 8 inches.
Wires connected to the battery and the tower measure speed, force, temperature and voltage. The entire test is managed by researchers from a short distance away using monitors to observe what happens.
So far, the team has tested single-cell and a 12-pack lithium-ion battery array.
Future improvements to the testing process will include adding springs or gas-pressurised pistons to boost the downward acceleration of the weight, increasing the impact force.
Stanley said: “Right now, we are accelerating at the rate of gravity. Our goal is to have a much higher rate of acceleration, thus more force.”
Click here to see a video of the drop tower in operation.