CETEK chargers

Mowbotman · Oct 30, 2023

During the winter months , especially were we live high in the Yorkshire dales, we get snow frequently, so the 2 small solar panels that are in my windscreen struggle to keep the leisure and vehicle batteries charged up , but summer months they are absolutely fine, so I have purchased a ctek charger and a powerbank , so the idea is to have a permanent connection to the vehicle battery and use the cigar lighter socket on the side of the kitchen to top up the batteries and alternate between the two batteries and plug into the power bank and bring the power bank back to the house when its needs charging, as I have no way of plugging into the main were it is parked , as anyone else tried this
Just had to fit a new vehicle battery at a cost of £280, so intend to loom after this one as best I can, it is also not convenient to keep taking it out for a run

Azteccamper · Oct 30, 2023

£280 - appears a lot. What size power bank are you looking to buy? They’re not cheap. I’m not technically brilliant but as you’re going up there to swop things around can’t you just take it for a spin to sort vehicle battery out? And once fully charged leisure batteries should be ok for 4-6 weeks without any problems.

Mowbotman · Oct 30, 2023

Ctek chargers that look after batteries that are fully charged do not take a huge amount of current, so not a problem there , so using fuel and wear and tear for an un necessary trip , and losing a parking space here is an pain in the arse no thanks, my option for me is better

Azteccamper · Oct 30, 2023

Mowbotman said:
Ctek chargers that look after batteries that are fully charged do not take a huge amount of current, so not a problem there , so using fuel and wear and tear for an un necessary trip , and losing a parking space here is an pain in the arse no thanks, my option for me is better

Sorry, I wasn’t doubting your idea but even a small draw on a power bank quickly uses its energy (we use one for charging phones, iPads, etc. when not on ehu) so I was just thinking about what size powerbank would be required for longer term use. The other thing with our powerbank is when things are fully charged it switches itself off (it was fairly cheap), so might be worth checking. Good luck.

Viktorgeorge · Oct 30, 2023

Mowbotman said:
Ctek chargers that look after batteries that are fully charged do not take a huge amount of current, so not a problem there , so using fuel and wear and tear for an un necessary trip , and losing a parking space here is an pain in the arse no thanks, my option for me is better

There has been a slightly connected string here:

Thread 'Long term hook up'
https://vwcaliforniaclub.com/threads/long-term-hook-up.51655/

I have the advantage of an adjacent power plug, but your basic approach is similar in that you want your batteries kept at or close to 100% for peak function and optimum longevity.

My vehicle is newer with three batteries and only the VW built in charger, but I am guessing that will be CTEK or very similar.

Elsewhere on the forum members have posted about the inefficiency of taking a DC power bank and using its 240v AC inverter for a CTEK to charge at 12v but if you have no alternative, it should still work.

The only question is how long the power bank will last at ‘trickle’. My initial analysis shows my T6.1 with three batteries fully charged draw 2-3KWh per week (perhaps £20-30 over 12 months). Depending on the KWh output on your power bank it would be interesting to hear how will your proposed system works before the power bank needs a recharge.

yossarian · Oct 30, 2023

Mowbotman said:
I have no way of plugging into the main were it is parked

The specifics of whether your powerbank can power your ctek I leave for you.

From an energy perspective you can expect battery self discharge of around 4% per month and it's well documented here that the vehicle battery is good for 5+ weeks standing around. Worst case on those numbers you need around 0.76kWh per month into the batteries. Assume 80% charging efficiency means about 0.94kWh energy you need to transport with a battery bank per month at a worst case. Show us the actual kit and I'll try run the numbers for you.

I have a similar problem with my van and I get by with 100W PV on the roof, the two busses bridged together with a 30A resettable breaker and a BM2 battery monitor I can monitor remotely.

Hueyhew · Oct 30, 2023

Just a thought for others who might be looking for a similar solution, I have tried one of these in the past on a motorhome stored away from mains: https://www.ctek.com/uk/battery-chargers-12v-24v/vehicle-type/car/solar/cs-free

With it's built in power bank it saves having the losses of an inverter, can be used to jump start and is a smart charger when on mains. It will need top up depending on drain but that can be down on the move via cigar socket.

Mowbotman · Nov 3, 2023

1st trial, it was a new battery so not sure how long The AA patrol man has had in van and the state of charge, plugged into my 300Watt battery inverter and it spent most of the day doing its stuff fine, from about 08:30 till around 15:00 , at this point it had got the batterie to the float charge ( not maintenance) So i was happy with that , so i could perhaps do the same thing every 4 weeks , and in between leave the small solar panel connected

Azteccamper · Nov 3, 2023

Mowbotman said:
1st trial, it was a new battery so not sure how long The AA patrol man has had in van and the state of charge, plugged into my 300Watt battery inverter and it spent most of the day doing its stuff fine, from about 08:30 till around 15:00 , at this point it had got the batterie to the float charge ( not maintenance) So i was happy with that , so i could perhaps do the same thing every 4 weeks , and in between leave the small solar panel connected

I was looking at the Ecoflow website and they have some good ’refurbished’ deals atm.