Charging Gel Batteries - 220v/Alternator/Solar Considerations

[demonboy]

I've just discovered that I can get hold of Exide Gel batteries. I've never used gel before and I'm keen to entertain them as an option. However I understand the dangers of frying them by over-charging. I need to get my head around four areas and am hoping someone could just confirm I have this right:

1. Mastervolt 12/40 240v mains charger
My Mastervolt 12/40 mains charger has some jumpers I swap over to compensate for gel charging though it seems to group together gel/wet battery as one option, with the other two being 'forced float' and 'diode compensation'. The instruction manual says 'by removing the gel/wet battery jumper the output will be a constant 'trickle charge' voltage of 13.8v. I understand gel batteries are floated at a higher rate (13.8). So, assuming I find the following jumpers am I to remove the top one in the middle column?

2. Sterling Pro AltC Split Charger
This is a simple rotary function switch I turn to 'gel. However it appears to split these into US Spec and EU Spec. What is this and how can I determine which the gels from India fall in to?

Also, I now have a sealed lead-acid starter battery and gel house. Does this unit handle the different batteries?

3. Balmar Alternator Regulator
I've yet to purchase this but I am sure I'm able to set the paramters for gel ok.

4. Steca PR 2020 Solar Regulator
I have this as my solar regulator and there is an option to set this for 'gel', so I'm hoping I'm ok here.

Are there any other considerations I have forgotten?

 

[Plevier]

It is dangerous to generalise too much about batteries. Different makes and models even of nominally similar types do have different charging requirements. If in doubt go by what the battery manufacturer says not the charger manufacturer. Some charger manufacturers have some odd ideas! (My Cristec charger has some absolutely ludicrous output options.)

However it's not too much generalisation to say you need to take great care if you mix SLA and gel. Their charging requirements will be different. You will need separately controlled outputs to handle them decently. It's easier to mix SLA and wet or gel and wet because wets are more tolerant.

On your charger, US spec probably means lead-calcium and EU spec probably means lead-antimony. It is probably a slightly higher voltage setting on US than on EU. If the gel batteries are Exide India then they are more likely to be antimony than calcium, so probably EU setting - but you really need to know Exide's recommendation and compare it with the charger figures.

So sorry, I can't answer your questions definitively. Nobody can without detailed knowledge of the hardware and batteries you have got, and i know that detailed info can be hard to get hold of.

 

[vyv_cox]

I would not dispute that what Troubadour says is exactly right. However, I had until very recently three open cell acid domestic batteries and an AGM starter battery. All are charged by either my Sterling controller on the lead acid setting or by my solar panel controller that has no variable settings. The mains charger normally only charges the domestic bank but can be used for the starter. I am careful not to charge the AGM for excessive lengths of time but despite the poor charging treatment it receives it remains in good health. It is now three or four years old and seems fine. The open cell batteries have been replaced by sealed ones and the Sterling settings changed appropriately, which should give the AGM an easier time.

 

[Plevier]

I would not dispute that what Troubadour says is exactly right. However, I had until very recently three open cell acid domestic batteries and an AGM starter battery. All are charged by either my Sterling controller on the lead acid setting or by my solar panel controller that has no variable settings. The mains charger normally only charges the domestic bank but can be used for the starter. I am careful not to charge the AGM for excessive lengths of time but despite the poor charging treatment it receives it remains in good health. It is now three or four years old and seems fine. The open cell batteries have been replaced by sealed ones and the Sterling settings changed appropriately, which should give the AGM an easier time.

Yes I'm counselling perfection and you may get away with less! Also peoples' batteries are often in a much worse state than they think they are; they only notice when they suddenly have to call for a deeper than habitual discharge and find they can't get it.
AGMs are terrific as starter batteries and if as oversized as small yacht batteries normally are, will do the job even if in much less than ideal condition. What will kill most AGMs is if you have more than about 14.4V for a lot of the time. You probably don't.

 

[demonboy]

Also peoples' batteries are often in a much worse state than they think they are

So, so true. Sadly most of what you say is moot as I cannot get hold of AGMs, as I think I have said before. I could ship them in but that would cost a fortune.

Since you're here, personal opinions on sealed lead-acid versus gel for domestic? I know the basic benefits and differences but has anyone had any experience of gel? I've just received the usual curt response from Charles Sterling who says

gel and sealed charge at the same profile so there is no problem, however i would not use gel batteries as the are over sold, expensive and useless

The price I have for 100aH gels are about GBP120.

 

[Plevier]

I wouldn't be quite as outspoken as Mr Sterling but I'd only consider gel if I couldn't get a flooded battery or if I was paranoid about leakage and couldn't get an AGM!
As I said before "Some charger manufacturers have some odd ideas!"
I still find it hard to believe any SLA will give the same life as a GOOD wet battery but some reports are good and I admit there have been design advances since I left the industry. At the time ours were top of the market and BT approved supposedly with a 10 year life (standby not cycling) but ...
A high temperature environment leans me even more towards wets.
There is an Exide India subsidiary that does make SLA batteries
http://www.sfindustrial4u.com/ no idea how good.

 

[demonboy]

OK, I'm confused now. I understood gel batteries as being a great solution for the marine environment from what I've read. I've also read, however, conflicting reports on gel and their performance in higher temperature environments, but they can be cycled 1,000 times, versus 300 or so for SLA. Considering that I'm looking for the convenience of a maintenance-free solution, why should I avoid gel?

 

[Plevier]

Flooded batteries range from cheap thin plate starter batteries that will give you a rotten cycling life through to expensive heavy duty ones with a good cycle life.
Gel batteries range from cheap thin plate fire alarm batteries that will give you a rotten cycling life through to expensive heavy duty ones with a good cycle life.
AGM batteries range from cheap thin plate starter or fire alarm batteries that will give you a rotten cycling life through to expensive heavy duty ones with a good cycle life.

I don't know what you're looking at and whose claims you are believing. 1,000 cycles under what conditions?

Gel have to be discharged with care and recharged with care (and generally slower than other types) and if you get it wrong they are ruined. AGM also needs some care but can be recharged quickly. Wet are the most robust.

High temperatures are bad for any lead acid battery but they particularly exacerbate the charging fussiness of gel and SLA.

Is topping up occasionally really intolerable?

How long are you staying in India? Long enough to try and claim under warranty if the expensive gel ones don't last?

 

[demonboy]

I don't know what you're looking at and whose claims you are believing. 1,000 cycles under what conditions?

Is topping up occasionally really intolerable?

How long are you staying in India? Long enough to try and claim under warranty if the expensive gel ones don't last?

I've no idea of the conditions of the cycles. This is half the problem with researching battery manufacturers I've never heard of before (Indian). What I have read is that the SLA batteries here have been designed with the tropical environment in mind.

Dare I admit it but I once had open lead-acid non-branded truck batteries and they lasted me less than two seasons. In order to fit them in my boat one had to be placed in a really difficult area to access (a low cupboard) and was nigh on impossible to check properly. As a result I was never able to top them up efficiently. Whilst many people using this forum have grown up with lead acid batteries, I find them a hassle (I've owned one car in my life and that was for two years only). I'm prepared to pay a little extra, or lose one year's worth of battery life, for the sake of a maintenance-free solution.

I appreciate your comments, Troubadour, and as a consequence of your comments, Sterling's and my research I think gel are now out the window, at least whilst in India. This thread may appear inconclusive but you've helped me thrash out some ideas and force me to do some research.

It seems, however, that my original claim that AGMs are not available in India is not true. I have found a manufacturer with an outlet in Cochin and yes, I'll be here long enough to ensure they last longer than the warranty. However if they prove to be too expensive I'll probably just settle for SLA once more and just be aware that I may have to change them again in three years time. As usual this is a price/performance compromise scenario with tight budgetary constrainsts. I only entertained the gel option as they appeared to be very cheap by European standards.

So, possibility of AGMs or back to SLAs manufactured for the tropical environment. Either way I think I need to spend more of my energy in solving an efficient charging circuit because that has been the main cause of my woes.

 

[noelex]

I've just discovered that I can get hold of Exide Gel batteries. I've never used gel before and I'm keen to entertain them as an option. However I understand the dangers of frying them by over-charging. I need to get my head around four areas and am hoping someone could just confirm I have this right:

1. Mastervolt 12/40 240v mains charger
My Mastervolt 12/40 mains charger has some jumpers I swap over to compensate for gel charging though it seems to group together gel/wet battery as one option, with the other two being 'forced float' and 'diode compensation'. The instruction manual says 'by removing the gel/wet battery jumper the output will be a constant 'trickle charge' voltage of 13.8v. I understand gel batteries are floated at a higher rate (13.8). So, assuming I find the following jumpers am I to remove the top one in the middle column?

2. Sterling Pro AltC Split Charger
This is a simple rotary function switch I turn to 'gel. However it appears to split these into US Spec and EU Spec. What is this and how can I determine which the gels from India fall in to?

Also, I now have a sealed lead-acid starter battery and gel house. Does this unit handle the different batteries?

3. Balmar Alternator Regulator
I've yet to purchase this but I am sure I'm able to set the paramters for gel ok.

4. Steca PR 2020 Solar Regulator
I have this as my solar regulator and there is an option to set this for 'gel', so I'm hoping I'm ok here.

Are there any other considerations I have forgotten?

I would look up the manufactures recomendations they do vary quite a bit between brands. When you have the correct bulk and float voltages (dont forget to compensate for temperatue) I would use a multimeter (with fresh batteriey in it, or even better a couple of multimeters) and see which settings give you closest to the required voltages.
I have Sonnenschein gel batteries and have had great life (16 years in one and 10-12 in the other). The sonnenschein web site has very detailed charging instructions Exide have taken them over and the Exide gels physically look similar (but they may be very different inside the casing)

 

[demonboy]

I have Sonnenschein gel batteries and have had great life (16 years in one and 10-12 in the other).

And this is why I am so confused. Why are people so down on Gel batteries when they clearly have the kind of longevity that is perfectly suited to the marine environment?

Troubadour - I have found that chart regarding comparison of battery types. It is in the West Marine catalogue and gel and AGM are compared thus:

Charge/Discharge cycles: Gel = 1000; AGM = 300

Surely when deciding on gel vs AGM the figures speak for themselves and gel is the clear winner?

 

[Plevier]

I note your comments about your particular conditions - difficulty of access etc. Of course they are all valid points for you that neither my nor Mr Sterling's comments are going to take into account because we're generalising.

Re the West figures - well they are just meaningless unless you know exactly which batteries they relate to and under what conditions and how failure is defined - complete failure or 80% residual capacity (that's the normal standrad for critical applications) or what? Are they verified technical results or just marketing blurb? Manufacturers literature rarely compares like with like, they choose unfair comparisons, and historically US literature has been (even) less impartial than European! The vast majority of gel cells won't do anything like 1000 cycles at any realistic depth. I'm not sure any will (unless they are tubular plates (generally OPZS range, which exist as wet and as gel but not as AGM) and I'm sure you won't be looking at those because of cost and size). On the other hand there are a few AGMs that will do more than 300. Most AGMs or gels (or wets) probably won't do more than 300 at any significant depth of cycle.

Of gels, Sonnenschein are probably the best. I'm fairly sure Sonnenschein invented the gel cell and they fought a long rearguard action against AGMs which almost everyone else regard as superior for most purposes. (Do the West figures originate from Sonnenschein by any chance?) However whether it's Sonnenschein or Exide or whatever, you have to bear in mind that all the big manufacturers have acquired existing companies and kept existing products, or set up new factories and introduced particular designs in those factories. It's not like a Ford Focus is a Ford Focus wherever you buy it regardless of name; it's more like when a GM car would be a Vauxhall here, an Opel there, a Holden the other side of the world etc and all different.

A battery out of an Exide badged factory in India (or Europe) is highly unlikely to be to the same design as an Exide USA battery. It could be good, it could be rubbish. However it's more likely to be good than one from a small indigenous manufacturer. Even different plants in the same country will be different! The group I worked for had 5 factories in Europe, all made different ranges often in competition. Some looked identical but were actually very different under the skin.

I'm sorry it's rather a lottery!

 

[demonboy]

Hi Troubadour - because I have found a possible supplier of AGMs I think I may go for these. I'm just awaiting prices and delivery...

 

[sailinglegend420]

.........I'm sorry it's rather a lottery!

To get a very good and seemingly fair comparison download the Lifeline AGM manual. At 34 pages this tells you everything you want to know about the differences between batteries. Lifeline used to make Gels but they are now very old technology (Sonnenshein 1957). AGMs have so many advantage that over the life of the battery they will prove to be the cheapest because their 30% less charge times cuts down on engine and genny fuel and maintenance costs.

Lifeline say 1000 cycles at 50% DOD, and 5000 cycles at 10% DOD!

 

[demonboy]

OK, works out at one UK pound per amp, slightly less if I go for the 120aH batteries. Sounds fair to me, though I cannot vouch for the quality. Suck it and see I suppose, the price is the same as what I bought recommended SLAs for in Turkey, and they only lasted me four years at a stretch.

 

[Plevier]

Yes I've seen the Lifeline manual before and it is excellent. As always the comparisons are somewhat biased and you should apply a correction factor to what they say in the columns "flooded", "gel" and "other AGM" in their tables! I can't fault what they say in technical text though.

Concorde were actually quite late adopters of AGM technology - well after us - but I've no doubt they make them well. I still find the cycle life claims very ambitious but I've had this discussion before on the forum, maybe with SailingLegend I'm not sure.

What make are the SLAs that you can get? Never forget that all SLAs are not made equal! Lifeline are undobtedly (among) the best. Incidentally the heavier the better for a claimed capacity as a first rule of thumb.

At the other end I would not touch E*****L with a barge pole but I doubt if those will arise in India anyway.

 

[noelex]

Different battery technologies have advantages and drawbacks. AGM batteries require frequent charging up to 100% for a reasonable life. This is difficult to do on many boats and in practice AGM batteries have a short to medium cycle life, at least with cruising sailors.
With deep cycle batteries, the quality of the battery, is a more important predictor of cycle life than the technology employed. AGM batteries are suited to boats relying on a generator for most of their electrical power ideally with frequent top ups on shore power.

 

[demonboy]

I've no idea of the SLAs here, Troubadour. I'd have to go shopping but the ones I have seen are not any make I've heard of before. Remember this is India, a country that is quite capable of building their own stuff with little requirement to import branded goods.

@noelex, I understand your argument about AGMs having short to medium life spans but your point about AGMs being suited to boats with generators to ensure they are frequently charged - how true is this really?

 

[Plevier]

Quote AGM batteries require frequent charging up to 100% for a reasonable life.
* No I don't accept that that is a significantly greater probelm with good AGMs than with other technologies.

Quote With deep cycle batteries, the quality of the battery, is a more important predictor of cycle life than the technology employed.
* Definitely agree!

Quote I've no idea of the SLAs here, Troubadour. I'd have to go shopping but the ones I have seen are not any make I've heard of before. Remember this is India, a country that is quite capable of building their own stuff with little requirement to import branded goods.
* If you can give the brand I may be able to find something out. It may be licensed. Yes I know India's capabilities, I have done a lot of business there. However in engineered manufactured products - cars,motors, batteries etc - the design and quality are still not usually up to the best world standards. Years of protectionism have fostered that and also led to low market expectations. I know it's improving!

 

[demonboy]

Well I can tell you the AGMs I was thinking of purchasing are made by Southern Batteries with the brand 'Hi-Power'. If you can find anything out about them I'd be grateful.