Recommended battery to battery charger for fogstar drift 105ah lithium battery?

[Gueyog8a7]

Even though I barely drive now, upon people's recommendations, a battery to battery charger does seem like a good idea to supplement my charging capabilities for these poor solar months. It would be good to always have it as an option without having to resort to shore power.

As mike fitz kindly ran some numbers in this post I was surprised to see how quickly it could potentially fully charge the battery. Within about 30 minutes of driving from that post.

The technical details specify 20a to 50a.

 

[mikefitz]

potentially fully charge the battery. Within about 30 minutes of driving from that post.

No, that's not what I suggested. I was attempting to show how power used by the heater over one day could be restored to the battery, not a full charge from empty.
The sums are easy, with fully discharged 100Ah battery and a 50 amp battery to battery charger it will take just over 2 hours. ( Provided the charger can deliver the 50 amps for two hours, often the units operate at below rated output due to temperature ).

 

[Gueyog8a7]

No, that's not what I suggested. I was attempting to show how power used by the heater over one day could be restored to the battery, not a full charge from empty.
The sums are easy, with fully discharged 100Ah battery and a 50 amp battery to battery charger it will take just over 2 hours. ( Provided the charger can deliver the 50 amps for two hours, often the units operate at below rated output due to temperature ).

Ok well 2 hours ain't too bad either!

 

[MisterB1959]

i have a Renogy DC to DC (or B2B) charger - its a 60A for a 304Ah fogstar leisure battery - i think most motorhomes will already give you around 15A per hour anyway - you do need to check re your vehicle alternator though ... if you go onto the Motorhome Fun UK forum, you will get some great advice specific to your 'project'

 

[Gueyog8a7]

Is it ok to buy a 60a charger then as 50a models seem rare and Mike says above they operate below listed rating anyway? Or should I get 40a instead?

 

[MisterB1959]

No idea, i only fitted it recently so it hasn't seen any realtime use other than one journey, to and from a location with free hook up as we were having some security enhancements. If it does operate below it's listed rating then I'm glad I went for the 60A version!

 

[Gueyog8a7]

No idea, i only fitted it recently so it hasn't seen any realtime use other than one journey, to and from a location with free hook up as we were having some security enhancements. If it does operate below it's listed rating then I'm glad I went for the 60A version!

What security enhancements? I want to look into this though has not been top priority yet as just living on my mums driveway while doing the main work.

I do get bad anxiety though when I have driven away and walk out of sight of my van. The more work I have done is the more afraid and invested I become in it so I am not even able to enjoy leaving it so it becomes like ball and chain. Even though the places I would be parking it is very unlikely to get stolen (rural UK) my mind is not at east. People have suggested more security for peace of mind.

 

[Gueyog8a7]

Guys my starter battery keeps running down since I am only driving about once a week and mostly stationary. Will dc-dc keep it topped up?

I suppose the issue is moot since to charge it I have to be running the vehicle and I can do that to charge the starter battery even without dc charger.

Having an option to top up with solar would be nice. I think this might not be a solution though because I am not even able to fully charge my leisure battery from solar let alone charge another source!

 

[MisterB1959]

@Gueyog8a7


yes, youre right, a DC to DC (B2B) only works when youre actually driving, so wont help if youre only driving once a week. you should look at the Battery master from vanbitz or if you do get solar, get an MPPT controller that also feeds your starter battery - i have a Votronic solar regulator which workd really well, often come up on ebay etc as people add more solar they need a bigger controller. they trickle charge about 1amp into your vehicle battery, which should be enough to keep it topped up until youre ready to drive off again.

Re the security enhancements, i had an alarm, immobiliser and tracker fitted by Vanbitz in the UK https://vanbitz.com/

they are NOT cheap, but prob the best on the UK market, for campers/motorhomes etc

i can recommend the Motorhome Fun forum in the UK; where you will get loads of great advice re your camper and adding/making improvements, its not free to join, but you can still read lots of posts and pick up most of the information you might need.

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