Here's an example of a well-secured battery in a firewall tray. We can't count the number of times we've seen batteries sitting loose or poorly secured under the hoods of vehicles. Face it......rope, bailing wire, or bungee cords are just not appropriate means by which to secure a battery. Acid spill from a loose or bouncing battery is one hazard. But having a high-current short under the hood where flammable liquids are present is not a good idea. We've seen a couple of fires caused by batteries shorting to nearby metal.