Which Metal Coatings Resist Car Battery Acid?

Glad you asked for suggestions and not answers.

I've never tried this stuff for acid resistance, but spray on undercoating is relatively cheap and might give satisfactory results.

Years ago, I impregnated nylon cloth (3-4 plys) with epoxy and applied that to the battery tray on my vehicle. Layered it up like I was making a boat. It worked well and lasted for years. If you really want acid resistance, epoxy/glass cloth would be even better.

In either case, adhesion may be marginal if you're putting it over rusty metal.

Good luck.

Reinforced poliester glass fiber .

A old empty car batery box that can hold the on use battery.

one of this material

CPVC A-Excellent plastic
Kalrez A-Excellent plastic
Kel-Fr A-Excellent plastic
LDPE A-Excellent plastic
NORYLr A-Excellent plastic
Polypropylene A-Excellent plastic
PPS (Ryton?) A-Excellent plastic
PTFE A-Excellent plastic
PVC A-Excellent plastic
PVDF (Kynar?) A-Excellent plastic

Vitonr A-Excellent plastic

PVC should be the easy to get.

Want metallic coating? If yes "lead" coating will withstand. A battery got lot of lead inside. I am using lead rod for level sensing of Sulfuric in storage tanks.

Gold, platinum work great!

If your idea is to cover the metal box, the options can be wrapping it with a medium micron polythene sheet cover or go for a glass fibre reinforced FRP coat which is acidity corrosion proof against Sulphuric acid. Polyethylene emulsion coats with epoxy resins can also be tried.

Hello Dennis,

Regardless of which coating you select, and before application, may I suggest that lead-acid battery charging voltages be checked. It is my understanding: once normal on-charge operating individual cell voltages reach gassing-voltage of 2.34 volts per cell, the cells, or maybe one cell has reached gassing (Hydrogen Peroxide Gas is produced) voltage ahead of the other cells, perhaps due to some type of high resistance. Also, if any or all cell water levels are over-filled, prior to charging, during the on-charge gassing period, the condition could be the cause for battery acid to be 'pushed-out' spilled onto battery tray.

May I also suggest: clean the metal tray, prime it, and spray it a couple coats of good spraypaint . Then keep the battery top and the metal tray dry. It should last a long time for good electrical service.

It sounds as though there is a containment problem in keeping the acid in the battery. This is the problem that needs to be fixed first.

I would have my doubts about polyethelene... Polyethylene works great as a half-cell separator in batteries. It allows the ions to pass freely between each half-cell without allowing the liquids to mix.

If the ions can reach each other within your battery compartment, it may still allow corrosion.

Lead. You can get lead spray paint from an electroplating store. It is sold to spray on plastic so that the part sprayed can then be plated.

Thanks to all who replied. I decided to use a coating of epoxy on the battery box for adhesion and acid resistance with a lining of heavy polyethylene film between the battery and the box for maximum protection.

Dennis Waller

Please ignore the 'input' from posts 3 & 9 ...

Lead works well in car batteries NOT because it resists corrosion, but because it corrodes very WELL in the application. (Remember: Most of the 'typical' batteries ARE, in fact, nothing more than a Corrosion Cell in action!)

Lead ... like aluminum and several other materials is AMPHOTERIC ... meaning that it will corrode MORE whether it is placed into EITHER an acidic OR a basic environment.

Carbon steels are not amphoteric; they will corrode faster in an acidic environment (moreso than in pH neutral), but, they are actually afforded some degree of PROTECTION from corrosion when put into alkaline (basic) environments. Application of cathodic protection to CS in seawater produces reaction product of hydroxyl groups on the CS surface, which are somewhat alkaline ... thus ADDING-TO the protection afforded by the polarization of same (by the anodes).

Just trying to "keep it real", gents ~~~