Is my new AGM battery cream crackered?

Afternoon everyone, hope everyone’s winding down for ‘Christmas’

This is my first post and have found so much useful information so far, I know a few of you guys are really clued up on 12v electrics so thought I’d see if anyone can help with my specific question.

I purchased a new 100ah Platinum Leisure AGM Plus batter from a big supplier, despite the retailer stating it would arrive fully charged, on arrival I hooked it up to a 5A smart bench charger and is was reading if I remember correctly about 11.8V and took about 12 hours to fully charge. Which would indicate it was fairly discharged to begin with and from what I have read on here and online, discharged batteries should be recharged as soon after discharge to prolong their life - and now i don’t know how long it had been sitting in the warehouse in this state?

emailed supplier who reassured the battery would be find and it was discharged because of delays due to COVID etc.

after fully charging the battery and taking a voltage reading at rest the next day the battery is sitting at 12.6v, I thought it should be a little higher. Now I’ve not used the battery ‘in the field’ but after hooking it up today, running the pump for 20 minutes and reeling in about 20m of hose with a Powerup3d, taking the voltage an hour later both with a multimeter and via a v16 controller it’s reading 12.4v

This seems to be too low for such little use, I’m not going to be able to get any real use to test it until after Christmas now but wanted to get your opinion on it before I contact the supplier again. Or am I just being concerned for no reason?

Thanks guys

I have stayed away from AGM batteries so don't know anything about them.

I believe they need a charger that will charge an AGM battery.

It could be that once the battery has rested the 12.4v you see may increase a bit. Different batteries react to loads differently.

12.7+ is supposed to be fully charged.

12.5v = 90% charged.

12.42v = 80% charged.

A lead acid battery needs to completely rest for at least 4 hours before an accurate volt reading can be taken to measure state of charge. It could well be the same with AGM.

The battery needs to be fully charged to begin with which yours doesn't seem to have been. What charger are you using?

spruce said:

I have stayed away from AGM batteries so don't know anything about them.

I believe they need a charger that will charge an AGM battery.

It could be that once the battery has rested the 12.4v you see may increase a bit. Different batteries react to loads differently.

12.7+ is supposed to be fully charged.

12.5v = 90% charged.

12.42v = 80% charged.

A lead acid battery needs to completely rest for at least 4 hours before an accurate volt reading can be taken to measure state of charge. It could well be the same with AGM.

The battery needs to be fully charged to begin with which yours doesn't seem to have been. What charger are you using?

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Thanks for the reply.

It's a Ctek smart charger with am AGM function. Just tested voltage again and its 12.37v.

Of a lead acid battery thay you are more familiar with arrived from the supplier as discharged as my AGM was, would you be concerned about its condition long term?

Mr BMP said:

Thanks for the reply.

It's a Ctek smart charger with am AGM function. Just tested voltage again and its 12.37v.

Of a lead acid battery thay you are more familiar with arrived from the supplier as discharged as my AGM was, would you be concerned about its condition long term?

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Probably yes.

I would have thought the voltage would go up, not down. I would leave your charger on it tonight and check it out in the morning. If its not up to voltage then I would ask questions about the battery not performing correctly. I would certainly give them these figures, first charge, first voltage reading before test, voltage reading after test etc and have them confirm in writing that they will action the warranty themselves if the battery prematurely fails.

However, if they are already skirting the situation by making excuses then I would take the problem to a higher source.

I have recently experienced that on line battery sellers take chances because they don't have to deal with you in person. Returning a faulty battery is generally at your cost even if the battery has a problem. You are then at their mercy when they tell you the battery has tested ok or its your fault the battery has failed.

I ordered a Numax. The one supplier didn't have it in stock, phoned me and offered a replacement which had a very poor rating. I cancelled the order and order on from Alpha Batteries as they had stock. No they didn't but sent me a Lucas battery replacement which was like for like. It was still invoiced as a Numax so now warranty is my problem - which it was with a Numax anyway.

spruce said:

Probably yes.

I would have thought the voltage would go up, not down. I would leave your charger on it tonight and check it out in the morning. If its not up to voltage then I would ask questions about the battery not performing correctly. I would certainly give them these figures, first charge, first voltage reading before test, voltage reading after test etc and have them confirm in writing that they will action the warranty themselves if the battery prematurely fails.

However, if they are already skirting the situation by making excuses then I would take the problem to a higher source.

I have recently experienced that on line battery sellers take chances because they don't have to deal with you in person. Returning a faulty battery is generally at your cost even if the battery has a problem. You are then at their mercy when they tell you the battery has tested ok or its your fault the battery has failed.

I ordered a Numax. The one supplier didn't have it in stock, phoned me and offered a replacement which had a very poor rating. I cancelled the order and order on from Alpha Batteries as they had stock. No they didn't but sent me a Lucas battery replacement which was like for like. It was still invoiced as a Numax so now warranty is my problem - which it was with a Numax anyway.

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Thanks Spruce, on charge tonight, will do some more testing and go from there.

online is really convenient but as you say, they have you by the balls when you need to pay for postage to return, I don’t imagine sending 25kg worth battery is cheap for the consumer

Mr BMP said:

Thanks Spruce, on charge tonight, will do some more testing and go from there.

online is really convenient but as you say, they have you by the balls when you need to pay for postage to return, I don’t imagine sending 25kg worth battery is cheap for the consumer

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If you have a bbl near you they are very good on price and  sell decent quality batteries 

Like as has been said, online battery sales can be tricky. 

This time last year I ordered two 12v 10ah batteries for one of my trolleys from an online seller. I think they were branded as Numax.  First time out I ran out of juice half way through the afternoon. Now I know that a fully charged 10ah battery will easily clear me a days work. So when I get home I take it off the trolley and by chance stood it next to the one it replaced and noticed it was half inch shorter. They had sold me two 7ah batteries but they had 10hr stamped on them. 

I once purchased 2x MK AGM Batteries for a large 100kva generator I owned. Got them online and when they turned up they were badly pallet wrapped onto a smashed up pallet.

The side walls of both Batteries were sucked in like they were held in a vacuum and one of the positive lead posts were completely snapped clean off.

They coat £299 each and spent days sending emails to the seller. I drove all the way from Devon to Leeds over night and camped in my van outside their warehouse. 

I was like a scrap yard and I think they were selling previously owned Batteries. Small claims court and trading standards later i got my money back.

I now only use local caravan and motor home camping suppliers locally 

If anyone needs a leisure battery then Euro Car parts have a great discount code. Just picked up a 110aH for £90.00

Apw1210 said:

If anyone needs a leisure battery then Euro Car parts have a great discount code. Just picked up a 110aH for £90.00

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They’re great as well if you need to switch it out. Just switched mine out and not a question asked

Apw1210 said:

If anyone needs a leisure battery then Euro Car parts have a great discount code. Just picked up a 110aH for £90.00

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For anyone who is interested they are listed here Euro Car Parts Leisure battery The discount code is FROSTY80