I bought a reconditioned battery for my 08 Mini Cooper S. The cars has been running and starting fine for the last 3 months but then was starting hard for the last week. Yesterday it was totally dead so I put it on the battery charger/maintainer (Noco Genius 10). It charged up fine within a few hours. The later in the day it started smelling like rotten eggs and the battery felt hot. It also was showing it wasn’t charging and was low. When I tried to start it today it was totally dead and only clicked. I brought it back to the store per the warranty and the guy said the battery had been totally drained. He said that something is draining the battery. He gave me another one but said until I find out what’s draining the battery, it will do the same thing with this replacement battery. Could the fact that the battery needed to be registered to the car cause this? The dealer told me that my year and model doesn’t need the battery registered. Why did the battery smell like rotten eggs?
Refurbished battery smelled like rotten eggs while charging and then died?
- Thread starter lokijoker
- Start date
The battery is old, sulfated and past it's prime. It's shot. When a battery cannot properly accept a charge the energy boils the battery producing gases, some of which, smell like rotten eggs. My guess is the battery you purchased was near the end of it's life when you got it.
The battery is shorted internally. Instead of reconditioned buy a new one.
If I remember correctly, that's sulfur dioxide.
As others have stated, the battery is toast.
As others have stated, the battery is toast.
Never, ever charge a battery that is hot to the touch. The rotten egg smell is hydrogen sulfate or sulfide, I forget which, and is bad news. It happens when the sulfuric acid solution is boiling inside the battery due to charging while there is an internal fault in the battery.
Use rubber gloves when you take the battery out and put it in a garbage bag to prevent acid damaging anything as it often spills out when it boils. Wear old clothes.
Use rubber gloves when you take the battery out and put it in a garbage bag to prevent acid damaging anything as it often spills out when it boils. Wear old clothes.
So I bought this battery from a shop that sells reconditioned batteries. They’ve been in business since the 70’s. We’ve bought batteries from them since then and have always had good luck with their batteries lasting over 3 years. I currently have one of their batteries in my Legacy that is over 5 years old and still going strong.
When I put it on the charger/maintainer in maintain mode it charged it up fairly quickly, in just a few hours and was keeping it maintained. When I went into the garage and smelled the rotten egg smell the lights on the NOCO Genius 10 Battery maintainer at the first stage red light like it was charging a dead battery. When I checked to make sure the clamps hadn’t come off and that’s when I could feel the battery was hot so I immediately unplugged it. About an hour later I tried starting the car and it did start but it dragged like the battery was low. The next day (yesterday) the battery was dead and it just clicked when I pushed the start button. So will a battery maintainer still possibly fry a battery or is that or short of problem with the battery?
So it was a short that caused it to fry or can a battery maintainer still fry a battery?
Sounds like you normally get new battery life out of used batteries on a regular basis. Time to buy a new used battery.
It at first charged ok and was in the maintain mode but the next day when I smelled the egg smell, it was in charging mode showing the battery at low level. Checking the clamps is when I noticed the battery was hot so I unplugged it immediately. I returned the battery and got another one. It didn’t leak any acid. But I’m going to have to return this battery because it doesn’t have the place to plug in the vent hose.
I got it replaced by the warranty they warranty their batteries for one year.
What I’m wondering is if this was caused because I should have registered the battery. BMW and Mini’s require their batteries to be registered or programmed in but I was told by the Mini dealer service that my year (08) doesn’t require that. But I’ve also been told that my model does need to have the battery registered and if it isn’t, it will cause the battery to fail prematurely because it will not charge it correctly. I decided to go by the dealer but maybe they were wrong.
You put the wrong kind of battery in it. You need an AGM, according to, well, you:
https://bobistheoilguy.com/forums/threads/wrong-battery-for-a-2008-mini.384785/
Put a new AGM in the car and stop using used lead acid batteries.
https://bobistheoilguy.com/forums/threads/wrong-battery-for-a-2008-mini.384785/
Put a new AGM in the car and stop using used lead acid batteries.
That battery was dead due to internal issues like a short or sulphation etc. Getting really hot while charging will usually produce a good YouTube episode. A good battery maintainer will shut-off when it senses a big problem, but your's sounds like it was still try to charge at a higher rate because of the dead cell. Which, depending on the charger, could be normal. With regard to the replacement registration and coding, why don't you check some of the Mini forums and get a good consensus about whether or not you have to register a new battery? Or check with a good indie and find out for certain. The battery you have may in fact have a plug in the port for the vent tube connection. If it is a proper AGM, some have plugs that you remove for connection. An AGM has to have some sort of venting mechanism in the event of internal failure that opens to let out gasses that that build up to dangerous levels so it won't explode. Lots of current ones have this vent built into the top caps used when filled and then a label is placed over them. This is what you are smelling. I get that you want to save a couple bucks on the battery and all, but at what cost to the damage it may cause?
*edited for clarification.
*edited for clarification.
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I love thrift and deals, and have had some times where cash is tight, but was not aware of this used battery market. This situation where you switch a battery, then replace with a used battery, then go and negotiate with the vendor for warranty coverage then place a third battery and it’s still a problem…. Life is too short.
We haven’t found a consistent consensus on this. Some forums and shops say you need to put an AGM battery in it. Others say you don’t and a lead acid battery will work just fine but might not last as long. The original equipment battery (Varta brand) lasted 12 years. But to replace it with the same battery would cost $350. The refurbished lead acid battery cost only $35.99 with a one year warranty. Like I said we’ve had nothing but good experiences buying refurbished batteries from this shop for over 40 years. If I knew we were going to keep the Mini for another 12 years I would probably spring for another $350 Varta battery or what ever Mini now uses in their cars but since we might not keep it that much longer I didn’t want to spend that much on an 08 car.
No.
There is consensus on this: use the correct battery for the car. You are refusing to accept that consensus.
AGM charges at a higher voltage, that’s part of why you are having a problem. You have already demonstrated what happens with the wrong battery.
Blowing this car up from an exploding battery will cost you a lot more than the Varta.
There is an old saying, “It’s the cheap man who spends the most”.
Your situation is clear proof of that - kill a car with a $35 battery? You cost yourself thousands, and risk personal injury, to save a few $$.
The battery maintainer is a 2 year old NOCO Genius 10 which is supposed to be a good maintainer which is highly rated. It’s worked fine since I bought it but maybe it’s suddenly not working right. My previous battery maintainer was a Battery Tender brand but it went out and I bought the NOCO because it was rated number 1. I didn’t think I had to worry about this kind of situation with a battery maintainer.
Again, the high charge rate may be a normal function of your charger, but I doubt it caused any damage or would allow for any to occur. It is normal for a maintainer type charger to "float" once charged, but it must be sensing something different and thinking the battery still needs charging at a higher rate. I'm not super familiar with the NOCO ones, but hear they are well rated. Might want to contact their tech support and get some answers with your issue.
Does it have a plain negative cable or does it have electronics on the negative cable?
A mini cooper s is turbo right?
A mini cooper s is turbo right?