Off grid night time battery charging? (1 Viewer)

[icantremember]

Well there has been a lot of advice given in this thread, but nobody has given the obvious suggestion ...

Fit another panel but make sure it's a lunar panel then you will have all situations covered ... unless it's cloudy!

 

[Spriddler]

When Paddy O'Meara suggested sending a space craft to orbit the sun he was told that it wasn't possible as it would burn up with the heat. "Simple" he said "Send it at night".

 

[Pausim]

Err-hum, would it not be easier to just pay for a mains hook-up for the night!

Otherwise, it all sounds way too complicated and expensive to me...

Some of my favourite pitches don’t have hook-ups.

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[Littlewheels]

I have an Efoy and it does just that. Charges whatever the weather, day or night and wherever you are parked. Including nice shady spots. I use 40 or 50Ah per day with a single 100Ah LiFePO4 battery. The Efoy runs quietly for 8-10 hours (no solar), turns on when the battery is about 40% discharged and stops when it is full. I need reliable electricity because I have a CPAP machine that runs all night. With the Efoy I simply don’t have to worry.

The Downside is it is not a cheap option.

I wouldn’t be without mine, bought some cartridges a month ago they came from Germany,cheapest, ordered Sunday and delivered Wednesday €8.50 delivery.

 

[mikebeaches]

Some of my favourite pitches don’t have hook-ups.

Well suggest visit them during summer, when there's plenty of solar and minimum electrical demand....

 

[Pausim]

Well suggest visit them during summer, when there's plenty of solar and minimum electrical demand....

My CPAP uses the same amount of power whatever the season and I like parking in nice shady spots in summer.

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[BusyBuilder]

We have 240w solar and two 85amp exide gel batteries. They are usually fully charged on the morning by 9am. But we aren't heavy users of batteries. More solar and better batteries is the answer

 

[mikebeaches]

My CPAP uses the same amount of power whatever the season and I like parking in nice shady spots in summer.

I'm no expert, but didn't think a CPAP used a lot of juice? But happy to be corrected.

 

[Pausim]

I'm no expert, but didn't think a CPAP used a lot of juice? But happy to be corrected.

The basic CPAP doesn’t use a lot but many users, like me, need to use it with a humidifier attachment which doubles the demand. It then has to run constantly for 7 or 8 hours and it mounts up. My overall daily power requirement including CPAP, water pump, lighting, heating etc. amounts to 30 or 40Ah per day. Whatever goes out has to be replaced.

Buying an Efoy is expensive but having an independent and reliable source of electricity is my priority. A CPAP shutting down unexpectedly in the night is very unpleasant. The daily running cost of the Efoy fuel is less than £5, which is about the same as an electric hook up adds to the cost of a pitch. For me it makes sense but I fully accept that for many solar is a better option.

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[autorouter]

Fit another panel but make sure it's a lunar panel then you will have all situations covered ... unless it's cloudy!

Lunar panels are soooo last year. The latest technology is the nebular panel, designed originally for tropical rain forest locations. As you know, many lunar panels are double-sided. To attain the required efficiency, nebular panels need to be triple-sided.

 

[autorouter]

Funny thing is, some Belgian freinds bought a new Hymer with one Lithium battery and two gel batteries, with the lithium there to top up the gels.

But seriously, the Hymer gel plus lithium system seems to use a small lithium battery in combination with a pair of gels. Some clever electronics makes the lithium battery do most of the small loads for most of the time, with the gels in reserve for larger loads or extended time off hookup/at night/bad weather. The lithium battery is better at continual charge/discharge cycling, and the gels are kept fully charged for the maximum time.

I think the OP needs the clever electronics module for this system to work. From the website they do a retrofittable version, but for MHs later than about 2012.

 

[Vic. Parsons.]

Perhaps you ought to have a battery to charge the battery to charge the battery to trickle charge the other batteries so you can keep the main batteries up!

So you're saying not to use a battery to charge another battery?
So how do you charge your cordless vacuum Cleaner, laptop, tablet, smart phone etc?
Presumably not off your leisure batteries through an inverter, because that would just be silly wouldn't it.

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[Vic. Parsons.]

But seriously, the Hymer gel plus lithium system seems to use a small lithium battery in combination with a pair of gels. Some clever electronics makes the lithium battery do most of the small loads for most of the time, with the gels in reserve for larger loads or extended time off hookup/at night/bad weather. The lithium battery is better at continual charge/discharge cycling, and the gels are kept fully charged for the maximum time.

I think the OP needs the clever electronics module for this system to work. From the website they do a retrofittable version, but for MHs later than about 2012.

Well that's me out then, our Hymer is 2002 so presumably our existing electronics would be incompatible.
Maybe I'll take a look at Lunar panels.

 

[Shrimp]

So you're saying not to use a battery to charge another battery?
So how do you charge your cordless vacuum Cleaner, laptop, tablet, smart phone etc?
Presumably not off your leisure batteries through an inverter, because that would just be silly wouldn't it.

I was actually being silly saying that about charging, I suppose if your sense of humour has gone then that would be a shame.
As to charging things like cordless vacuum that's on the inverter when travelling and all else is on USB ditto!

 

[Vic. Parsons.]

I was actually being silly saying that about charging, I suppose if your sense of humour has gone then that would be a shame.
As to charging things like cordless vacuum that's on the inverter when travelling and all else is on USB ditto!

I know.

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[jezport]

We only have a 140w panel mppt charging and the 2x 97ah AGM batteries are being charged fully each day. You should cope as you are, maybe you should add an extra battery and check your original battery is good.

 

[Mark and Mindy]

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[autorouter]

I'm not too convinced about your reasons for charging the lead-acid batteries from the lithium battery, but the answer to the original question is yes, you can easily arrange for the lithium battery to charge the lead-acid one.

As well as the stuff for charging the lithium from solar, you will need a B2B (Battery to Battery) charger. Usually a B2B works in voltage-sensitive mode. It charges the target battery when the source battery voltage rises above a threshold, which indicates it is being charged itself. But that's not what you want.

The B2B can be set to an alternative mode, where it uses the D+ wire from the alternator to sense that it is charging. So whenever the D+ wire is seeing 12V, is tells the B2B to charge. You could wire the B2B D+ terminal to a 12V supply via a switch. Then whenever the switch is on, the B2B will charge. The switch could be manual, a timer, or daylight-sensitive.

The B2B will continue charging until the target battery is full, or the source battery drops to a predefined low limit.

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