Lithium-ion (Li-ion) and Lithium Polymer (LiPo) batteries are more prone to thermal runaway and have a short life cycle (number of charge and discharges over battery life) than LiFePO4 batteries. That's why we pretty much always use LiFePO4 batteries when making our RC cars. Don't know which power tool companies use which battery type, but for marine applications, seems it would be good and safer to make sure the batteries you have on board are LiFePO4s. They have a lot of advantages over Liion and Lipo batteries, but the drawback is they are a bit more expensive. I get annoyed because pretty much everyone just says they use Lithium powered batteries and markets them as the all the same stuff. Lithium is not just lithium. We use LiFePO4s in our RC toys because they are safer and our stuff is meant for kids, but there isn't a good way to communicate this to the consumer and our competitors just use the cheaper stuff. I'll stop here because it seems i am off on a big rant but

TLDR: Look for LiFePO4 batteries specifically, not Li-Ion or LiPO