Gel Batteries v's Wet Lead Acid

[starvin marvin]

I've previously asked about this and It now looks like I'm going to need 2 new leisure batteries. The existing 85 amp/hr ones date from 2003 and are not holding their charge. The fuse next to the charging relay is also showing signs of overheating although it has not blown.

 

Can anyone confirm that wet batteries, amp/hr for amp/hr give longer in use service, ie I can stay away from hookup longer than with gel batteries. We did manage 12 days away from hookup last winter in Spain/Portugal and we want to do it again. In addition I'll try and fit larger wet batteries if possible say 110 amp/hr, I know venting is required.

 

This may seem daft but I just want to be as independent as possible without 1) Solar and 2) Generator. The first is possible but I think the consensus is that in the winter nothing very much is gained from solar. The second is I can't really carry a genny, simply no room, without major reconfiguration of storage.

 

Many thanks

 

 

 

[JohnP]

Gel batteries are considerably more expensive than wet lead acid.

 

From my experience there is little difference in how long each type holds its charge in service.

 

The charging regeme is different between the two types. Some chargers (eg in Hymers Electroblock ) have a switch which is selected according to the type of battery fitted.

 

Has your van got this capability?

[Guest Tracker]

Three 110 ah leisure batteries would still cost a heck of a lot less than a] a generator or b] solar panels and would be one possible solution?

[rowley]

AGM will be cheaper than a Gel.

[Derek Uzzell]

One of the advertised benefits of a gel battery is that its 'no load' discharge-rate is very low. However (to the best of my knowledge) if you take any sort of 12V battery, in perfect condition and fully charged, and apply a specific electrical load to it, then its rate of discharge will not be battery-type dependent. Simplistically speaking, if you take a 100Ah gel battery and a 100Ah 'wet' battery and apply a 5A load to each, after 5 hours both batteries will be 25% discharged, after 10 hours 50% discharged, etc.

 

JohnP's comment about different charging regimens being required for gel or wet batteries raises a issue that has always intrigued me.

 

It is certainly true that the charging regimen of many (most?) modern battery-chargers can be selected according to whether the battery to be charged is gel or 'wet'. The CB-516 charger installed in my Hobby has this facility and Hobby fit a gel leisure-battery. It would also appear from the literature that comes with the charger that a regimen appropriate for a gel battery might have the potential to harm a wet battery, and that the regimen appropriate for a wet battery might well not be capable of bringing a gel battery to full charge.

 

However, because we rarely use 230V hook-ups (unless they are free) my motorhome's on-board battery-charger has a very easy life. The Hobby's leisure-battery is normally recharged during driving via the vehicle's alternator and thus experiences exactly the same treatment in terms of charging-regimen as the vehicle's 'starter-battery' that is the usual wet type. I suppose this is OK as, presumably, the gel leisure-battery will be being charged using a 'wet' regimen (and the Hobby's gel battery hasn't actually exploded yet!), but I've often pondered over whether it wouldn't be technically preferable with a motorhome to have wet leisure-batteries rather than the gel type just so they match what I anticipate the base-vehicle's charging system was originally optimised to handle.

 

Personally, I'd much prefer not to have gel leisure-batteries, as replacements are less readily available and far more costly than 'wet' types. Trouble is Hobby, like many motorhome manufacturers employing the Ford Transit chassis, locates the leisure-battery beneath a swivelling cab-seat where it's impossible to carry out the regular checking/maintenance that a wet battery needs. (For what it's worth, Hobby also puts a swivel on the other cab seat, thus making the wet starter-battery equally inaccessible. Perhaps Hobby believes that the Ford-provided battery is immortal.)

 

[Brambles]

Some of you might fund this link intersting and may change your thinking about batteries. http://www.sterling-power.com/support-faq-2.htm

Jon.

[starvin marvin]

Thanks Bramble, food for thought. I never really understood what was special about Gel batteries, apart from the price.

 

I was hoping Clive would reply as I'm sure I've read an article by him advocating using wet lead rather than gel, and more batteries before purchasing a solar panel.

 

Thanks again

[Clive]

1) Wet is the most cost efficient but needs to be maintained and kept the right way up. Catalytic caps minimise maintenance by turning the gasses back to water.

 

2) Gell & AGM don,t need maintaining but will have a shorter life if regularly deep discharged. They should not be discharged as deeply as wet cell batteries.

 

3) Carbon fibre (Elecsol etc) are more tolerant to over discharge but hellish expensive.

 

If its your money and if you don,t plan to roll the motorhome then its option 1 with quality batteries.

 

A solar panel would be my next suggestion. 80 watt or more.

 

C.

 

 

 

[ned]

HI starvin'

 

The reason why you often get gel batteries on the leisure circuit of a motorhome is when it is positioned under the seat. 1) because it is pretty difficult to access and 2) because there is no gassing which needs to vented outside. In most cases where the batteries are put in outside lockers or garages etc, then they tend to be 'wet' cell batteries with vents through the floor of the battery compartment. Two or three 110 amp batteries will last a week and a half in summer but maybe half that time in the winter where you are using the heating fan, more lights and maybe Tv. DVD or radio. You can save quite a lot of energy by changing your background lights/bulbs for warm LED replacements. I wouldn't use them on reading lamps as they are not as bright. Hope this helps. Shop around on the web and you can get a 110amp leisure/marine battery for about £48-00.

 

Cheers.... Keep em waxed........... Ned

[mom]

Could I throw one more question in?... I purchased a lead acid "wet" 110 amp hour a while back, as a leisure battery.  Most of the batteries for sale had a small hole and a tube.  "For venting", I was told.  But I found one that didn't appear to have that small hole, and I was told "That one is sealed, so you don't need to vent.  I think."  In other words, the salesman wasn't totally sure it was a sealed battery, but he couldn't find a venting hole either.

 

My battery is located in the bottom compartment of a pantry locker in a VW Autosleepers Trident, which takes quite a while to access.  I can't seem to find any outside holes in the compartment cavity to allow gases to escape, but am "assuming" I don't need to worry.

 

Can anyone help me build confidence that it would be ok to install one of those intelligent chargers that manage charge and then maintenance cycle whenever hooked up tp 240v?

 

[Brambles]

Hi Mom.

Without details of brand and battery model number it is difficult t give an acurate answer.

Most batteries which are sealed, will say so on them. There are various possibilities. It could be semi sealed, and have catalysing cell caps that convert the gassses back to water. But they still need a safety vent which you would see somewhere. It is also possible it does vent, but vents through each of the caps around the edges of them.

Post the make and type number, model name etc and it can be checked what you have as there are numerous different options.

Jon.

 

[starvin marvin]

Thanks for the reply Clive. I've never heard of catalytic caps before, does this make them lower maintenance than regular wet batteries, if the gas turns back to water? Do you still have to make allowances for venting?

[Brambles]

I think one saftey aspect is often overlooked by users of Lead Acid Batteries. All batteries, be it wet, gel or sealed should be used in a well ventilated are or enclosure. Wet cells vented through a tube is fine to take exposive gasses outside, but under fault conditions all lead Acid batteries could produce excess amounts of Hydrogen and become explosive. Also note majority of sealed batteries are actually vented through a safety seal... a one way valve in effect, so under high charge of discharge conditions where the catalyst cannot convert all gasses back to water, then excess can escape from building up pressure.

In my opinion by far the safest option for use in a Motorhome is spill resistant (which majority are) wet lead acid with hole/nozzle for an external vent tube. Using a gell battery without an external venting is dangerous if gell setting is not used on charger, or under high discharge conditions.

[tp002c784tp002c784tp]

I think the answer to all our Battery problems would be Lithium Batterys once they conquere the problems they are having

 

Terry

[Clive]

Hi Marvin,

Brambles summed it up prety well.

Catalytic caps does make them lower maintenance than regular wet batteries as the gas turns back to water? Providing its charged properly.

 

A properly vented enclosure is always the safest bet.

[Brambles]

Terry,

 

Lithium-Ion Iron Phosphate batteries are already available, delivers twice the run time of the equivalent lead-acid battery pack, at a 35% weight reduction. Down side is cost, but they do come maintentance free.

 

 

[THE SHEPHERD]

Any tips on sites for Lithium-Ion as I can only find torch Batts. TS

[THE SHEPHERD]

I have just spoken to a supplier who tells me the batteries are a danger and she would not have one in a camper, not that she new what a camper was. TS

[neillking]

I've heard and understood all the theory about the different types but have to say my personal experience of fairly heavy use in motorhomes is as follows:

 

GEL: 100% bad. Every one I've had has failed early despite being on a proper GEL regime (including the Hymer one already mentioned)(also different brands at different times on different chargers etc).

AGM and Elecsol: Good and lasting ~5 years.

Wet/SFL: Fine and cheapest but sealed they've never been - except in a maintenance free sense.

 

One swallow doesn't make a summer as they say but I won't be buying any more GEL for myself.