How to bring dead leisure battery to life without mains?
Discussion
I live in my van and have a starter battery for the usual starting the vehicle and a leisure for the living as per the normal van build setup.
Last winter I accidentally ran the leisure down to 0% - read 4V on the meter when I checked later! This ended my off-gridding stint as I had to find a mains charger to bring it back to life again.
The problem was I was under the false impression at the time that the solar charge controller was self powered in that it would run off the solar coming in and so it would just put more charge into the battery the next day. This, of course, was not the case and only found out when I got power again and searched what went wrong.
I know you can get low voltage disconnects and I am considering getting one of those. I have a lithium for my leisure which apparently can happily drain to 0% but of course I don't want it that low for the above reason.
Since I got in that fix before I analyze the voltage of the leisure assiduously now but as such I get antsy when it goes to around 30%. In this case I had been advised I am leaving available power on the table and could safely discharge to 10% without problems.
Now low voltage disconnect is a good idea but I wondered, belt and braces, are there some hacks to bring it up again if it did deplete to nothing by some turn of events? I have a dc-dc charger as well and likewise to the solar charge controller it would not work either if there is not some charge on the leisure battery to power it.
Looking through options I had thought one way could be to get some hefty jump leads with high continuous rating to parallel the starter and the leisure battery but I abandoned this as many people were dissuading me online it could be dangerous and not worth the risk.
I saw about the Ctek CS Free but it seems a stupid concept, in my case, if not using mains, to charge that thing with the leisure battery or starter battery, to then charge the leisure back up again. I mean it is moving energy from one place to another so why not cut out the middle man, and the big price tag, and find some direct connect option to get just a little boost from the starter.
I have just got a trickle charger from leisure to starter to keep that topped up but I am wondering now how I could trickle the other way, only in case the leisure deflated to unusable state as of course in usual situations it can just be boosted with the dc-dc charger.
I read about the cigarette port boosters the other day. I am wondering, if I got a port for the leisure battery, if that would work to plug to the van's port and then one connected to the leisure. Maybe that wouldn't work though due to the higher resting voltage of lithium vs sealed lead acid of the starter? It seems that would give the same trickle charge like the extortionate CS Free for a fraction of the price at only £20.
Any other ideas or ratifying of ones above?
I suppose it is not an issue if I did get a low voltage disconnect but nice to know. The more strings to the bow the better. In off gridding I have found that having plan B, C and D are often important as your best intended plans can often go out the window.
Last winter I accidentally ran the leisure down to 0% - read 4V on the meter when I checked later! This ended my off-gridding stint as I had to find a mains charger to bring it back to life again.
The problem was I was under the false impression at the time that the solar charge controller was self powered in that it would run off the solar coming in and so it would just put more charge into the battery the next day. This, of course, was not the case and only found out when I got power again and searched what went wrong.
I know you can get low voltage disconnects and I am considering getting one of those. I have a lithium for my leisure which apparently can happily drain to 0% but of course I don't want it that low for the above reason.
Since I got in that fix before I analyze the voltage of the leisure assiduously now but as such I get antsy when it goes to around 30%. In this case I had been advised I am leaving available power on the table and could safely discharge to 10% without problems.
Now low voltage disconnect is a good idea but I wondered, belt and braces, are there some hacks to bring it up again if it did deplete to nothing by some turn of events? I have a dc-dc charger as well and likewise to the solar charge controller it would not work either if there is not some charge on the leisure battery to power it.
Looking through options I had thought one way could be to get some hefty jump leads with high continuous rating to parallel the starter and the leisure battery but I abandoned this as many people were dissuading me online it could be dangerous and not worth the risk.
I saw about the Ctek CS Free but it seems a stupid concept, in my case, if not using mains, to charge that thing with the leisure battery or starter battery, to then charge the leisure back up again. I mean it is moving energy from one place to another so why not cut out the middle man, and the big price tag, and find some direct connect option to get just a little boost from the starter.
I have just got a trickle charger from leisure to starter to keep that topped up but I am wondering now how I could trickle the other way, only in case the leisure deflated to unusable state as of course in usual situations it can just be boosted with the dc-dc charger.
I read about the cigarette port boosters the other day. I am wondering, if I got a port for the leisure battery, if that would work to plug to the van's port and then one connected to the leisure. Maybe that wouldn't work though due to the higher resting voltage of lithium vs sealed lead acid of the starter? It seems that would give the same trickle charge like the extortionate CS Free for a fraction of the price at only £20.
Any other ideas or ratifying of ones above?
I suppose it is not an issue if I did get a low voltage disconnect but nice to know. The more strings to the bow the better. In off gridding I have found that having plan B, C and D are often important as your best intended plans can often go out the window.
Maybe this seems laughable, but if you happen to park near flowing water could you not have something rigged up where you have an alternator or some sort of small generator driven by a paddle wheel you could lower into the water, a long lead from alternator to your leisure battery.
I've not tried this myself as not a van lifer, but any way of using what comes naturally and free from govt intervention (theft of your money under the guise of taxes) should be worth exploring.
I have a very old small output Honda generator here, 12v and 240v, its almost silent running, you can find them used for very little.
I've not tried this myself as not a van lifer, but any way of using what comes naturally and free from govt intervention (theft of your money under the guise of taxes) should be worth exploring.
I have a very old small output Honda generator here, 12v and 240v, its almost silent running, you can find them used for very little.
Perhaps not the answer to your question but here is my experience.
I have a motorhome with a 200w solar panel & 2 x leisure batteries & can comfortably achieve 90%+ off-grid with just the running of the engine while travelling to supplement this.
I have a 2.5kw inverter for mains duty & rarely have I seen charge levels as low as 50%. I have a 1.5kw coffee machine that is the biggest draw which is used several times a day along with other less powerful things and an AC unit which I occasionally use for an hour "after tea" to cool the motorhome down as the day is cooling down.
The charge controller does all this in its stride without intervention whilst also keeping the vehicle battery charged to a level that supports the vehicle side of things.
My understanding is that the charge controller takes the available solar electrical energy & puts the vast majority into the leisure batteries whilst topping up the vehicle battery if/as required.
Perhaps your issue is the actual leisure battery is goosed, just asking if this is possible.
I have a motorhome with a 200w solar panel & 2 x leisure batteries & can comfortably achieve 90%+ off-grid with just the running of the engine while travelling to supplement this.
I have a 2.5kw inverter for mains duty & rarely have I seen charge levels as low as 50%. I have a 1.5kw coffee machine that is the biggest draw which is used several times a day along with other less powerful things and an AC unit which I occasionally use for an hour "after tea" to cool the motorhome down as the day is cooling down.
The charge controller does all this in its stride without intervention whilst also keeping the vehicle battery charged to a level that supports the vehicle side of things.
My understanding is that the charge controller takes the available solar electrical energy & puts the vast majority into the leisure batteries whilst topping up the vehicle battery if/as required.
Perhaps your issue is the actual leisure battery is goosed, just asking if this is possible.
DrDeAtH said:
Small wind turbine perhaps? It would maintain the leisure battery in low light conditions
Yes there are all sorts of ways to do provide power but I want to know tricks if it bottomed out. I know prevention is best but it is a just in case thing.Just like you always aim to have a battery that has enough charge to start yet there is still a large market for jump starters.
Smint said:
Maybe this seems laughable, but if you happen to park near flowing water could you not have something rigged up where you have an alternator or some sort of small generator driven by a paddle wheel you could lower into the water, a long lead from alternator to your leisure battery.
I've not tried this myself as not a van lifer, but any way of using what comes naturally and free from govt intervention (theft of your money under the guise of taxes) should be worth exploring.
I have a very old small output Honda generator here, 12v and 240v, its almost silent running, you can find them used for very little.
Like this?I've not tried this myself as not a van lifer, but any way of using what comes naturally and free from govt intervention (theft of your money under the guise of taxes) should be worth exploring.
I have a very old small output Honda generator here, 12v and 240v, its almost silent running, you can find them used for very little.
https://www.amazon.co.uk/BaiLiWang-Generator-Water...
zalrak said:
Trust the Chinese to sort it, a bit bigger and more obvious than what i had in mind...which was something where the genny could be hidden on the bank and the water wheel driving it via a piece of alloy tubingWhy not just buy a small 500w power station, a lot of those can be charged from a solar panel directly via an XT60 connector. Then just plug a battery charger into the power station when required to boost up the leisure battery.
You also gain the benefit that you would have another 500w of power available, to run lower wattage stuff like a small tv, lighting etc.
You also gain the benefit that you would have another 500w of power available, to run lower wattage stuff like a small tv, lighting etc.
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