Charging battery Without mains

[Clearview Lee]

Hi Guys…

Is it possible to charge a leisure battery other than directly from a mains socket as I may be moving from my house into a flat.
The last thing I want to be doing is taking the battery up flights of stairs to charge it, then down again in the mornings. ? is there some kind of power pack I can charge, then leave in the van overnight to charge the leisure battery?? ?

I’ve tried SCRelay which didn’t really work for me when I first tried initially years ago.

Thanks in advance fellas.

Kind regards

 

[dazmond]

I live in a first floor flat....I have an extension lead from my landing plug socket,down my stairs,through my letterbox out to my van....I also have a SCR fitted...

You need access to electricity mate so I'd think carefully before moving...?

 

[scottish cleaning service]

I use a Festool Power Station which is great but burnt out 2 now. I'm on the third one and if it goes the same way then I get my money back.

 

[ched999uk]

You could try solar panels on your roof. 2 x 80 watt ones with an MPPT controller should give about 10 amps per hour in full sun, but maybe only about 2 amps per hour in the winter!
Solar isn't ideal but it might help put some charge back in the winter and a full charge in summer I would guess. You would just have to keep your eyes on the voltage.

Another alternative would be a different type of battery. If the pump pulls 6 amps over 6 hrs that's 36 Amp Hrs. So a 50AH LiFePO4 (can be discharged to 20% capacity) battery is only 7kg but about £250! Then you need the correct charger so that's about £40. That would mean carrying the battery in each evening but at 7kg it's a tad easier than a leisure battery at 25kg!

 

[Pjj]

Hi Guys…

Is it possible to charge a leisure battery other than directly from a mains socket as I may be moving from my house into a flat.
The last thing I want to be doing is taking the battery up flights of stairs to charge it, then down again in the mornings. ? is there some kind of power pack I can charge, then leave in the van overnight to charge the leisure battery?? ?

I’ve tried SCRelay which didn’t really work for me when I first tried initially years ago.

Thanks in advance fellas.

Kind regards

Solar panel on the van roof at this time of the year should help not saying it would fully charge it but should certainly boost charging rate @spruce maybe able to advice on this ??

 

[scottish cleaning service]

You could try solar panels on your roof. 2 x 80 watt ones with an MPPT controller should give about 10 amps per hour in full sun, but maybe only about 2 amps per hour in the winter!
Solar isn't ideal but it might help put some charge back in the winter and a full charge in summer I would guess. You would just have to keep your eyes on the voltage.

Another alternative would be a different type of battery. If the pump pulls 6 amps over 6 hrs that's 36 Amp Hrs. So a 50AH LiFePO4 (can be discharged to 20% capacity) battery is only 7kg but about £250! Then you need the correct charger so that's about £40. That would mean carrying the battery in each evening but at 7kg it's a tad easier than a leisure battery at 25kg!

I have a 4kw system on my roof, best thing I have did concerning energy. Went to buy some of the new Sunpower ones with the inverter built in but sold out. Next stage is Lithium ion batteries and swap over to heat pump and remove my gas meter so I will be all electric. This seems to be the future for homes.

 

[Pjj]

I have a 4kw system on my roof, best thing I have did concerning energy. Went to buy some of the new Sunpower ones with the inverter built in but sold out. Next stage is Lithium ion batteries and swap over to heat pump and remove my gas meter so I will be all electric. This seems to be the future for homes.

He is looking at charging a battery in his van not a pv roof mounted array on a house

 

[spruce]

Solar panel on the van roof at this time of the year should help not saying it would fully charge it but should certainly boost charging rate @spruce maybe able to advice on this ??

There is another windie on the other forum who put 2 solar panels on the roof of his van. He lives on the south coast. His 2 panels did keep his battery fully charged during late spring, summer and early Autumn. From October to late March, his solar panels did nothing of any consequence. Once he said all he managed to put back into his battery was 1 amp during one winter's day. His solar controller was a Victron Mppt controller, top quality when compared with the cheaper PWM controller that isn't as efficient. His daily commute was 10 miles from home, and he often got stuck in traffic. Even with a split charge relay his alternator never fully charged his leisure battery. Later, when his van battery needed replacing, he decided to use his Numax combo leisure battery as the main battery and run his pumps from that. It didn't make things better.

His conclusion was that solar was a waste of time for him.

We have a holiday camp site with a caravan storage facility. One caravanner found that the output of 1 solar panel on his caravan roof wouldn't even keep his caravan battery fully charged during winter. He invested in an additional 3 panels which he propped up in the front window to just keep his batteries charged.

I've linked this before, but it's well worth a look at the results of solar in winter on a narrow boat. David was in the Midlands somewhere when he made this video. For us, I have a Battery to battery charger on board. Even with this, we can sometimes be down 10 to 15 amps at the end of the day.



As you watch this, look at the angle his solar panel are tilted to. To secure panels on the roof of a van, they need to be mounted flat to protect them.

 

[scottish cleaning service]

Panels are getting better all the time. Mine are 15% efficient and the new Sunpower are near 24% efficient but I think they are sold out. I read they are developing a 40% efficient panel which doesn't involve silicon. Early days but with high energy prices this will grow even faster because the demand will be there. Tilt and turn panels following the sun will be the next big thing. November, Dec, Jan and Feb are a waste of time for me because I'm lucky to make 1 Kw per day from a 4Kw system. I have a wind tunnel between my building and the neighbours where a turbine would be perfect if there was no noise from it. Also have a stream running down a 100 foot hill which is another source of making energy. Up here we are surrounded by possibilities but not many take advantage of it, till now.

 

[spruce]

You could try solar panels on your roof. 2 x 80 watt ones with an MPPT controller should give about 10 amps per hour in full sun, but maybe only about 2 amps per hour in the winter!
Solar isn't ideal but it might help put some charge back in the winter and a full charge in summer I would guess. You would just have to keep your eyes on the voltage.

Another alternative would be a different type of battery. If the pump pulls 6 amps over 6 hrs that's 36 Amp Hrs. So a 50AH LiFePO4 (can be discharged to 20% capacity) battery is only 7kg but about £250! Then you need the correct charger so that's about £40. That would mean carrying the battery in each evening but at 7kg it's a tad easier than a leisure battery at 25kg!

I believe a lithium battery would help as it would accept a much higher charge than a standard lead or calcium acid leisure battery does. This would mean that the alternator might be able to do the job. However, from my limited knowledge, a 50 amp Lithium-ion battery should only be recharged with a maximum charge rate of 50 amps. (1C). So in theory, taking 20 amps from this battery would mean it could be fully recharged in about 20 to 25 minutes. This higher charger rate could hammer the alternator. A temperature sensor is usually fitted onto the alternator and if the alternator gets too hot, the charge rate is cut until the alternator cools.

Winter is another issue, as you can't charge a lithium-ion battery when it's 0 degrees or below, although you can still draw power from it.
But @ched999uk I believe you know more about this subject than I do.

I think another real issue is going to be not being able to keep his van frost free. I don't know where @Clearview Lee gets his water from, but if he has an r/o on board, protecting that r/o from frost is a major concern without electricity.

 

[ched999uk]

I was more thinking that a LiFePO4 battery was light weight that could be carried in each night to recharge. As you mentioned they don't like being charged when cold and lose a bit of capacity when used in the cold, so maybe a bit more capacity than 50A would be advisable.

As you say @spruce trying to recharge a battery quickly onboard does produce a few issues!