Battery upgrade

[Ian0354]

We have a 2002 Rapido 941m which has a 110amp leisure battery at the moment. We normally wildcamp and visit the shows so mostly camp without hook up and despite having a solar panel of, I’m guessing, about 60 watt judging by its size the battery didn’t hold up very well over the last few times we’ve used the motorhome so we seem to need replacement. We’re considering upgrading our battery from the 110 and, by making a small alteration to its placement to give some more space, we’ve thought of buying a Varta LFD180. We’ve read that the Varta LFD batteries get good reviews on the forum but we wonder if there would be any problem with the one big battery on the few times that we are on hookup as the charger technology is now quite old. Would forum members advice one big battery rather than a pair of, say, LFD90? We want to increase our leisure bank as preparation for some possible cold weather camping where the blown air might be asked to work hard.

 

All opinions welcomed.

[aandncaravan]

It isn't just the Mains charger capability that should be examined when increasing the battery bank size, but the entire cabling, power controller, etc durability.

The webpage below shows photographic images of damage/fires where a second battery was added without the owner doing their homework :

http://www.aandncaravanservices.co.uk/add-a-second-battery.php

 

[Derek Uzzell]

Ian

 

Allan’s website covers the technical aspects involved in adding a second leisure battery, but you may also need to consider size and weight.

 

I remember talking to a representative of Wokingham Motorhomes years ago when they were the sole UK Rapido agent and all Rapido A-class models were Mercedes-Benz based. I mentioned doubling up the leiure-batteries and he said that, on some 9M series sold on a 3500kg chassis, payload was so restricted that adding a 2nd battery could be the final straw. The other thing he mentioned was that Rapido had seemingly not allowed for the weight of a pair of batteries and that the result of one owner’s modifications to allow the battery compartment to accept two batteries had been for the compartment complete with batteries to fall through the motorhome’s floor.

 

The cost and weight of a Varta LFD180 will be roughly the same as the cost/weight of a pair of Varta LFD90s, though the latter will cover more ‘floor area’. However, lifting and manoeuvring a single 45kg LFD180 is likely to be a good deal trickier than handling each 25kg LFD90 individually. There’s also the potential to retain a workable leisure-battery system should one of the LFD90s develop a fault, whereas if a LFD180 becomes faulty you’d have no usable leisure-battery system.

 

Personally, I favour the 2 x LFD90 approach if room can be made to fit them in, but I can understand the attraction of a single ‘biggie’ if it’s a lot easier to accommodate it.

[Ian0354]

aandncaravan - 2018-02-15 10:29 AM

 

It isn't just the Mains charger capability that should be examined when increasing the battery bank size, but the entire cabling, power controller, etc durability.

The webpage below shows photographic images of damage/fires where a second battery was added without the owner doing their homework :

http://www.aandncaravanservices.co.uk/add-a-second-battery.php

 

Thank you for your comments, this is exactly why we asked the question. There is some evidence that a previous owner had, at some time, connected a second battery in the adjacent underbed locker but of course we have no way of knowing what the total battery bank was. We will be studying your website in detail although advice will be taken as, although quite capable of altering the cabinetry to accommodate the battery (batteries) we will not attempt the wiring.

[Ian0354]

Derek Uzzell - 2018-02-15 3:33 PM

 

Ian

 

Allan’s website covers the technical aspects involved in adding a second leisure battery, but you may also need to consider size and weight.

 

I remember talking to a representative of Wokingham Motorhomes years ago when they were the sole UK Rapido agent and all Rapido A-class models were Mercedes-Benz based. I mentioned doubling up the leiure-batteries and he said that, on some 9M series sold on a 3500kg chassis, payload was so restricted that adding a 2nd battery could be the final straw. The other thing he mentioned was that Rapido had seemingly not allowed for the weight of a pair of batteries and that the result of one owner’s modifications to allow the battery compartment to accept two batteries had been for the compartment complete with batteries to fall through the motorhome’s floor.

 

The cost and weight of a Varta LFD180 will be roughly the same as the cost/weight of a pair of Varta LFD90s, though the latter will cover more ‘floor area’. However, lifting and manoeuvring a single 45kg LFD180 is likely to be a good deal trickier than handling each 25kg LFD90 individually. There’s also the potential to retain a workable leisure-battery system should one of the LFD90s develop a fault, whereas if a LFD180 becomes faulty you’d have no usable leisure-battery system.

 

Personally, I favour the 2 x LFD90 approach if room can be made to fit them in, but I can understand the attraction of a single ‘biggie’ if it’s a lot easier to accommodate it.

 

Thank you for your comments Derek, you make some interesting points that will be given considerable further thought. As you say the LFD180 is a big beast but it appeals for, amongst other things, getting rid of one set of wires and connections, we can accommodate it fairly easily and after reading your comment we would reinforce the floor before fitting it. SWMBO has read Alan’s website and now favours that we simply replace like for like, ie at 110amp and see how we go for now. We use very little power, all LED and very very seldom use TV plus we’re not late night people, it’s just the worry of running out of power for the blown air.

[Derek Uzzell]

French-language archived Rapido technical specifications can be found here

 

http://www.rapido-camping-car.fr/rapido_historique-technique_les-anciens-guides-techniques-rapido.phtml

 

In 2002 it seems that Rapido were standardising on a single 90Ah leisure-battery, with no factory-option to specify a 2nd battery.

 

Might be worth you identifying the make/model of 110Ah battery you currently have. This would allow forum comments on its perceived merits (or otherwise) and what you might best replace it with.

 

If Rapido was fitting a 90Ah battery in 2002, the space allowed for it was probably not over-generous. If the Varta LFD route were chosen, there’s a significant ‘dimensional’ step up from the LFD90 (353mm(L) x 175mm(W) x 190mm(H)) to the LFD140 (513mm(L) x 189mm(W) x 223mm(H)) so - unless you modified the battery compartment - you’d probably have to opt for the LFD90 that is ‘rated’ at 90Ah not 110Ah.

 

That’s just an observation, but if you are considering like-for-like replacement based purely on your present battery being labelled as 110Ah, you’ll need to be careful not to pick a run-of-the-mill 110Ah battery when a superior 90Ah battery (eg. the Varta product) would be the better choice.

[aandncaravan]

Ian, Now that you are aware of the loadings and limitations, you are probably better equipped than most to adequately manage a bigger battery bank without issue. Therefore I would suggest that a LFD140 would be a reasonable compromise. Remember the LFD range place a lighter load on the charging systems than most other batteries because of their extra efficiency, so you can get away with a bigger battery than the usual limits.

 

 

Just try and limit how low you discharge it, as it is when it is both deep discharged down to say 70% DOD (only 30% charge left) and/or the battery bank being allowed to get beyond it's best that loadings become very high on the charging systems. Consider using 12.3v as your minimum discharge level.

 

The LFD 90 is sold in large numbers so likely to be fresh when bought from the usual suppliers recommended on this Forum. However, I would imagine the LFD140 is a slower seller so might have been on the shelf at the suppliers longer? Suggest you double check the battery is at a decent charge level when it arrives at you door, as some can get a bit discharged suffering degradation? Suggest you consider refusing it if it is below 12.6v on an accurate meter.

 

Also be careful when placing bigger batteries on concrete/rough surfaces as the extra weight makes it easier for a sharp stone/lump to crack the casing. The surface where you unpack the battery must be ultra smooth.

We have had 3 reports now of bigger batteries leaking from base cracks from suspected incorrect handling when unpacking. With a big heavy battery, even a small stone can penetrate the case..

 

 

 

[Ian0354]

Derek Uzzell - 2018-02-16 8:39 AM

..........

In 2002 it seems that Rapido were standardising on a single 90Ah leisure-battery, with no factory-option to specify a 2nd battery.

 

If Rapido was fitting a 90Ah battery in 2002, the space allowed for it was probably not over-generous. If the Varta LFD route were chosen, there’s a significant ‘dimensional’ step up from the LFD90 (353mm(L) x 175mm(W) x 190mm(H)) to the LFD140 (513mm(L) x 189mm(W) x 223mm(H)) so - unless you modified the battery compartment - you’d probably have to opt for the LFD90 that is ‘rated’ at 90Ah not 110Ah.

 

That’s just an observation, but if you are considering like-for-like replacement based purely on your present battery being labelled as 110Ah, you’ll need to be careful not to pick a run-of-the-mill 110Ah battery when a superior 90Ah battery (eg. the Varta product) would be the better choice.

 

Thank you again Derek, very useful to be able to read the original spec. Given that most buying new in 2002 would have managed most likely useing the original fitment halogen lamps which we save on with LEDs plus our very limited use of TV we are tempted to think again and revert to factory spec and replace the battery with one good 90amp, ie a Varta LFD90. We have noted from both yours and Allan’s comments regarding the 110 versus Varta 90 products. We have concerns after reading Allan’s webpage more thoroughly and our thinking is that, being a continental MH, there must have been owners who used their Rapido when they went skying and presumably managed for periods using the blown air from the factory fitted leisure battery.

 

We hope to be able to change to a 983M in three or four years time so hopefully this new arrangement will get us through till then. We only bought this MH last spring when we returned to the hobby after some years enjoying other interests plus from this year we want to tour for longer using aires, etc, so we have no experience of how long a fresh battery will run the MH.

[Ian0354]

aandncaravan - 2018-02-16 10:23 AM

 

Ian, Now that you are aware of the loadings and limitations, you are probably better equipped than most to adequately manage a bigger battery bank without issue. Therefore I would suggest that a LFD140 would be a reasonable compromise. Remember the LFD range place a lighter load on the charging systems than most other batteries because of their extra efficiency, so you can get away with a bigger battery than the usual limits.

 

 

Just try and limit how low you discharge it, as it is when it is both deep discharged down to say 70% DOD (only 30% charge left) and/or the battery bank being allowed to get beyond it's best that loadings become very high on the charging systems. Consider using 12.3v as your minimum discharge level.

 

The LFD 90 is sold in large numbers so likely to be fresh when bought from the usual suppliers recommended on this Forum. However, I would imagine the LFD140 is a slower seller so might have been on the shelf at the suppliers longer? Suggest you double check the battery is at a decent charge level when it arrives at you door, as some can get a bit discharged suffering degradation? Suggest you consider refusing it if it is below 12.6v on an accurate meter.

 

Also be careful when placing bigger batteries on concrete/rough surfaces as the extra weight makes it easier for a sharp stone/lump to crack the casing. The surface where you unpack the battery must be ultra smooth.

We have had 3 reports now of bigger batteries leaking from base cracks from suspected incorrect handling when unpacking. With a big heavy battery, even a small stone can penetrate the case..

 

 

 

Thank you for your advice Allan, I’ve learnt a lot over the last couple of days from reading your webpages. As you can see from my reply to Derek, as we’ve no experience of how this MH would manage with a new battery plus given the possible risks and fire hazard it is now our intention that before altering the cabinets, and following careful thought, to revert to factory spec and fit 1 x Varta 90LFD and hope this gives us what we need. I note your remarks on DOD and will monitor the battery carefully. We hope to be able to upgrade our MH in three or four years so we might look at enlarging the leisure battery bank then based on the experience gained from this battery change.

 

BTW, As a teenager back in the late 1960’s I was told that the quickest way to “kill” a lead acid battery was to stand it directly on a concrete floor so this is something I’ve always avoided doing. There is most likely no scientific reason behind this, it’s probably an old mechanics tale but still from what you’ve written it does no harm to keep remembering what I was told ;-)

[Derek Uzzell]

See following links

 

https://www.homepower.com/articles/solar-electricity/equipment-products/ask-experts-batteries-concrete

 

https://www.snopes.com/autos/techno/battery.asp

 

(Plenty more if you GOOGLE on “battery concrete floor”)

 

Regarding your earlier comment “...our thinking is that, being a continental MH, there must have been owners who used their Rapido when they went skiing and presumably managed for periods using the blown air from the factory fitted leisure battery”, I suspect that many Rapido owners in the early-2000s who were contemplating winter-sports motorcaravanning, or longish stays off 230V hook-up, would have recognised the limitations of the standard 90Ah battery and just fitted a 2nd one.

 

Nowadays the internet is awash with information/advice on almost any subject one can imagine, and there’s plenty of discussion on non-UK motorhome forums about installing multiple leisure-batteries. But use of the internet was less universal when your Rapido was built and people then just modified their motorhomes without the in-depth advice that’s easily available now. Most of the time they probably got away with it...

[Ian0354]

Derek Uzzell - 2018-02-17 9:10 AM

 

Regarding your earlier comment “......... I suspect that many Rapido owners in the early-2000s ........would have recognised the limitations of the standard 90Ah battery and just fitted a 2nd one..........Most of the time they probably got away with it...

 

Derek, We are most anxious that we don’t fall into the group that don’t get away with it! 8-) :'( , we’ll manage.

 

With apologies for the way in which I’ve edited your comments.

[Ocsid]

At this time of the year, if roof mounted a solar panel will be way off performing well as the sun angles are so low, weather generally overcast and light hours short.

This coupled to a bigger power demand for more heating, more use of lights and probably longer TV viewing hours, all contrive to make solar at best a challenge in the winter.

 

Is there any possibility that you issue presently in the winter lays more with the charging capacity than the battery capacity?

[Ian0354]

Ocsid - 2018-02-17 1:29 PM

 

Is there any possibility that you issue presently in the winter lays more with the charging capacity than the battery capacity?

 

Hi, Yes I think there is every chance this is the issue but, having read through Alan’s very thorough website and seeing the damage that can be done by asking too much of the vehicle alternator, we feel unsure of fitting more battery capacity to a vehicle with electronics that don’t have the advantage of modern, higher, capacity. As you say solar isn’t the answer in winter so, having excluded a generator as a way forward, we’ll just have to consider moving the MH more often when wilding in cooler temperatures. To be fair the only time we are sat still for four days when it might be cool is at a show so that is the longest we have to manage for. One thing we will be doing is getting either a thicker or a suplimentary cable installed on the supply to the leisure battery to help.