You cannot just put a battery in your car, leave it there and drive. That battery might fall over and cause some serious problems to your car. You need a battery tray to secure the battery from falling over or shifting. A battery tray uses bolts, bars and other devices to keep a car battery in place.
There are many varieties of battery trays designed for great style and maximum security. However, all these designs have one common enemy: corrosion. Battery trays tend to rust relatively quickly compared to other car parts because of the water and battery acid that eats away at them. Car owners usually complain of rusty trays that are unattractive and useless. Choose a battery tray that is protected from corrosion so that you don’t have to replace it. Plastic trays prevent rust and are very light. There are also stainless steel models which also prevent corrosion and are more durable
If you do not want to buy a new battery tray, you can simply restore your old one. First, take out the tray by unbolting the one and a half inch bolts that secure the battery. If they are also rusty, use a lubricant so they will come off easily. Now, check the tray for damage. A tray that is full of holes is beyond repair. However, if there is only minor damage or corrosion on the tray, you can still restore it.
Use aluminum oxide to remove the rust from the metal. Do not concentrate on one area alone because you might burn through the metal. Lightly pass over the entire surface and make sure all the rust is removed. Next, coat the tray with rust-inhibiting primer and paint it. Finally, polish the surface with an abrasive and put on the final color coats. The restored battery tray should function for a couple more years.
If the battery tray is beyond repair, buy a new one that you can use for a long time. There are models that are resistant to movement, vibration and shock. High-end models cost more but you will eventually spend less on their maintenance.