Pajero Owners Club of South Africa

After never having seen this phenomenon on any of my batteries before I noticed the positive of my auxiliary battery was severe. I also noticed that the plastic coating on one of the connectors on the positive from the controller was deformed. Thinking it was arcing because the connection was loose I checked buy it doesn't seem the case. No evidence of any heat buildup anywhere else.

What us causing this sudden sulphation?

Sent from my half-eaten fruity mobile device!

No bright spark cough cough able to offer an opinion?

Well no, I wouldn't be able to help, BUT! I am very interested to find out the reason, as well as a solution to this. The deformed plastic must result in heat right? Thus is the Aux bat laboring .... I know to little, but its scary

If only you had a half decent camera to post some pics, it could have helped.

The cause of the build-up (all of a sudden) has me stumped.
I have a way of dealing with the build-up, but I don't think that's what you are after.

Sulfation/sulphation is a build up of lead sulphate crystals on the battery plates during the normal charge/discharge cycles.

I don't think that is what you are referring to.
I think you are referring to the accumulation of acidic crystals on the terminals, which forms when acid vapours cause corrosion of the metal.

This problem should not happen if you have a sealed battery (good reason to get sealed battery).

I solve this by covering the terminals with a mixture of grease and bicarb of soda (1 tablesppon grease + 1 teaspoon of bicarb, well mixed).

Gerhard, thats not nice to talk about his Canon like that...

Gerhard

Yes it's a build up of crystals on the terminals.

It's a deltec sealed auxiliary battery, so should not be leaking (unless it got damaged, but not sure how that's possible)

I'm wondering if my battery is starting to go belly up.

SimonB wrote: It's a deltec sealed auxiliary battery, so should not be leaking (unless it got damaged, but not sure how that's possible)

Clean it properly and check for dampness on the seams (= leak).
Acrid acid smell during charging is often a dead give away.
If you have litmus paper (ask your chemist for a few), put a damp one near the terminals. Acid fumes will change the colour.

With what do you charge it?
Alternators do this to aux. batteries (over-charging).

4ePajero wrote: With what do you charge it?
Alternators do this to aux. batteries (over-charging).

It's been in my engine bay for 4 years... why now?

The alternator sees the two batteries as one, so when one battery's internal resistance changes, the alternator will act as if both have the same characteristics, and charge accordingly.

it is a known fact that the rapid charge rates associated with alternators are not ideal for deep cycle batteries.

Good time to consider a CD-DC charger for the aux. battery?

Mitsubishi Garage spray's mine every time I take it for a service, with a aerosol can with something in it to prevent it Maybe go past them and ask them or give them a call.