https://langa.com/index.php/2020/05/...m-ion-battery/
I try to be early. I store my two 500 Ah bicycle batteries in an original, used military ammo box cal 7.62 when they are not in use, I also never store them with more than 50% charge. With half their load it still is a lot of energy (500 instead of 1000 Ah). I have no idea whether the box will help anythign if one of the batteries should turn grumpy. I store them in a place away from the household with all that easily burning stuff.
I store other, smaller lithium batteries (for camera, telephone for exmaple) again in thick metal boxes with sturdy sealing.