I'm not 100% positive, but I don't think so. They are using prismatic cells with electrolyte vent on top and if you store the batteries on their side there is a potential for leaks. Since I'm not 100% sure, I wouldn't have ordinarily replied but since no one else did I thought I'd give my opinion. SOK is very responsive to emails sent to them for questions. I would ask them what they have to say.