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Left my batteries on charge. Connected to Accumate pro charger. Set to 24 volt.
Both batteries are bulging and melted together. Any idea what could have caused this. They were in the tank at the time but no damage done.

Hello



You have most likely charge with to high amere.

or charge the batteries separately on 12v


Stefan Ohlund

Overcharging of batteries causes heat build-up. If the charger misses the fact the battery has reached its peak capacity, it keeps pumping in energy, which can only be dissipated as heat.

I have to say I'm losing faith with my Accumate. I left a couple of batteries on charge one evening and the charger was quite happily running in "Absorb" mode. At about 4AM, it suddenly switched into full bulk charging mode and woke the pair of us up. I switched it off at that point, mainly because of the noise it was making. The following morning I switched it back on and it did the usual Bulk -> Absorb -> Maintain routine and the batteries appeared to charge OK.

On other occasions, when I know the battery is discharged, the charge simply flicks between Absorb and Maintain and never charges the batteries.

I do a lot of work with UPS devices which use similar batteries to us. It is fairly common for old batteries, which have been left in the device long after they have been reported as bad, to swell so much that they are impossible to remove.

Adrian

John,
In my two Armortek tanks I use two 12V batteries wired in series which makes their combined output 24V. Is your system two 24V in parallel which would double the available amps, or two 12V in series which would double the available voltage (to 24V)? I cannot tell the voltage of each, but it looks like they are wired in series.

Two things which may have occurred; somehow each battery charged at 24V, when it should have been 12V or perhaps the polarity was incorrect (reversed)from charger to batteries? There have been instances where people have blown up car batteries when they try to jump start the car by crossing the polarity from the doner car to dud car(red from charged to black of uncharged, red from uncharged to black of charged). You can also blow the fuses in your Armortek switch box pretty fast if the polarity is connected wrong from the batteries to electronics. These look like the new sealed gel type batteries which may have prevented them from exploding.

I'm always worried about over charging or damaging the electronics so I remove them and charge them separately to 12V. Its slow. I would assume the charger you used was intended to charge the whole system connected together, but something failed within the charger or the polarity was incorrect at the connection points.

Perhaps someone with more electrical experience than me can shed some light on how best to set up charge points etc (isolate them from the metal hull) and charge the system in one set up?

Unfortunately I think you may have to buy new batteries and perhaps a new charger too.
Best regards,
Bob

I will take them out and charge 2 in 12 v mode in future. Luckily no damage beyond the batteries. Polarity. I know there was a short powercut while they were in charge mode. Maybe this had something to do with it. BEST BE CAREFUL. CHARGE OUTSIDE THE TANK.

Hello John,

I use a C-TEK charger Multi XT 4000 24 volt it is not a cheap charger 163 pound but
i think its one of the best chargers you can get.
I use 2 Panasonic batteries 12V 22 Ah and i charge them together, the batteries are
fully charged after 5,5 hours in the normal charge mode and the batteries donth get warm.
There are also different charge modes on the C-TEK
best regards Yves

Hello John, I also use the Accumate charger and charge my two 12v batteries inside the Comet. When I first set up my batteries, I noticed that the standard Tamiya type two pin plug supplied with the Accumate, was wired the wrong way around, when matched to Tamiya Plugs.
All Tamiya type plugs have the same set up, ie,square end positive.
I telephoned the guy at Accumate, and he said....thats how we wire all our chargers.
So, I made up a short lead to match the Tamiya plug fittings with the Accumate fittings. Just check the Accumate wiring. I remember the guy also saying that the lead with the 'ridge' on the wire is positive, as both Accumate wires are black on my charger, not red and black.....Mick.

Thanks mick, bothe rires on the charger lead are indeed black but one has a small red marker at the end. Which lead has the fuse? It charged fine before. How long should it take to charge the two batteries in 24 volt charge mode? 2 12 volt 22 amh batteries.

Hello John, my fuse is on the red positive lead in the tank, not sure how long to charge fully. I keep my batteries 'topped up, each week....which only takes a few minutes. Electrics are a black art for me.....however I remember having this 'which lead is which' problem, last year.....Mick.

Thanks mick. I will have a good look at this later. So much for smart charger.

Hi Guys
I think you will find that Acumate have a bit of Red on the eylet end of their
charging lead and this should follow back to the one with the fuse.
I use connectors in my battery power line so I disconnect the battery every time after switching off and its always disconnected on charging.
The hunting from one charge stage to another I experienced once on my new T34-85
batteries and the instructions say if this persists it could be sulphating of the plates
I think that was their words,but this was on allegded new batteries,so it might depend
on how long the supplier has the batteries in stock and how they treat them.
I havent had the problem again and I recharge similar to mick and deffinately on the
Yellow light of the power supply.
Cheers
Phil

Hi,

I've a number of Accumate chargers and use them on 24v and I normally leave them connected all the time. The connectors are the opposite way round to how Tamiya connect theirs but they are 'industrial' connectors so I guess each user can have them either way round. If you use the supplied charge lead (with the rubber cap and fuse) then it's not an issue.
I find that the larger the battery, the longer (relatively) it remains on bulk and less on 'absorb'. It is hard to say how long it takes to charge, as it depends on battery size and how low the battery is but they don't often stay on 'bulk' for much more than a couple of hours and if the tanks have been used for a couple of hours will normally get to 'maintain' in less than 3-4 hours.
Also be aware that when they get to 'maintain', that is not an indication that they are charged to their maximum, just that they charge rate has dropped to the lowest level. You really need to leave them on maintain for a while to fully charge - I would normally reckon on leaving them charging at least overnight.

I have a pair of Enersys Racing Extreme 30 batteries, they are a new version of the SBS30 batteries. Not exactly small or cheap, but they do allow fast charging. I have never had a problem, but with the charger I have, a Sealey super charge 30/1, it has a number of settings which allow you to charge at different rates. It has been known to damage one of these batteries by setting the charge rate at max. This will squirt 30 amps in to begin with and drop as the battery charges. From the state of the batteries it looks like they have been over charged, but that is based on what I have seen in the past.

Generally I don't level the tank on charge for long periods, and I check that state of charge using a 4qd battery meter in the tank, and touch wood I have not yet had a problem. But as John says with the accumate, I had a different version for my Harley, which was left on most of the time as I never rode it much, never had a problem. And Harley's eat batteries.

Do not think its a wiring problem as it worked fine before and wiring not changed. I think the charger is still under waranty so will try to have it checked. It is supposed to be possible to leave this connected all the time with out overcharging. I leave my bike permanently connected and never had a problem so might be a charger issue.

Thanks everybody for all the help. I have another set of batteries so will try them but keep an eye on them.

Do not think its a wiring problem as it worked fine before and wiring not changed. I think the charger is still under waranty so will try to have it checked. It is supposed to be possible to leave this connected all the time with out overcharging. I leave my bike permanently connected and never had a problem so might be a charger issue.

Thanks everybody for all the help. I have another set of batteries so will try them but keep an eye on them.