This Southern California solar farm is using retired EV batteries for storing the power and then send to the grid when needed. This way the retired batteries can extend their usefulness for several…::A Southern California company is showing how repurposing EV batteries for stationary storage can extend their usefulness for several years.
I wouldn’t be as worried about oxygen, but more worried about properly sealing the container off as a water leak could cause the lithium in the battery’s to produce hydrogen.
But the odds off either happening are very slim.
Edit: the water has to come in contact with the lithium.