Battery charging without mains power..

woody1144

Junior Member
Messages
35
Hi, hope you are all keeping healthy.

My Granturismo is currently SORN at my parents in the garage as where I live doesn't have mains power for my CTEK. Obviously with the weather getting nicer I want to be reunited with my love but alas I don't have mains where I currently live. From previous experience, leaving the maser without being driven for a week or two starts screwing with the electrics due to low voltage (parking brake issues, power steering etc, the usual). I'm not keen on disconnecting the battery each time as I'm sure this can't be good for the electrics and fear that the F1 gearbox will hate me for this.

I've been thinking for a while about how to get around this issue and have stumbled across this:

https://www.ringautomotive.com/en/product/RCB320

Does anyone have any experience or envisage and issue with using this on the car once a week to top up the battery? It has a slow trickle function which I think would be safe and it seems to get good reviews...
 

midlifecrisis

Moderator
Messages
8,417
A cheap and simple way is to use an old battery to add capacity. Charge up the old battery at home, for 24 hours, and then connect it to the car's battery via jump leads. It won't upset the electronics, the battery will effectively double the capacity and you can easily remove it for another recharge.
 

spkennyuk

Member
Messages
4,506
Hi, hope you are all keeping healthy.

My Granturismo is currently SORN at my parents in the garage as where I live doesn't have mains power for my CTEK. Obviously with the weather getting nicer I want to be reunited with my love but alas I don't have mains where I currently live. From previous experience, leaving the maser without being driven for a week or two starts screwing with the electrics due to low voltage (parking brake issues, power steering etc, the usual). I'm not keen on disconnecting the battery each time as I'm sure this can't be good for the electrics and fear that the F1 gearbox will hate me for this.

I've been thinking for a while about how to get around this issue and have stumbled across this:

https://www.ringautomotive.com/en/product/RCB320

Does anyone have any experience or envisage and issue with using this on the car once a week to top up the battery? It has a slow trickle function which I think would be safe and it seems to get good reviews...
Thats a bench charger. It still needs to be plugged in to charge your battery.

Your only options if you have no way to get 240 volts to a trickle charger would be a solar battery maintainer.

Something above 10 watts should maintain the battery if it was fully charged when parked up.

Ideally find a way to run the cable through from the back seat / rear shelf to the battery so that you can leave the solar panel on the rear shelf when charging and remove when your driving. The cables normally plug into the panel so you only need access to the fly lead to plug the panel in and tuck out of the way when not needed.

The higher the wattage the better it will maintain the charge on the battery.

Its not a perfect solution as we dont have ideal solar conditions in this country but it should extend the period of time you can leave the car without the battery / car being used.

Something like this may suit your situation better.

 
Last edited:

rs48635

Member
Messages
1,689
as above ^^ use an 'old battery' when car is in darkness.
The solar charger might help. The cable will likely survive trapped in the boot opening with unit resting on the roof?
I have solar unit but gave up using it because I did not bother connecting through to the battery. Had hoped that cigar lighter socket in armrest was always live, but it soon times out. Not sure the output was usefully high anyway.
 

woody1144

Junior Member
Messages
35
Ahhh yes, Monday morning combined with lack of caffeine = one special post... I can't believe I missed that it wasn't a battery pack haha!
Thanks for the suggestions everyone, much appreciated. I think the "old battery" method is going to be the most suitable as my parking is underground. I've seen Harry Metcalfe using the solar charger on that Sl600 he had in France which worked a treat but unfortunately won't for me :(.

I don't have an old battery but no worries buying a new one. My concern I guess would be leaving the jump leads on it unattended with the battery hanging out of the boot. Could there be a fire hazard or anything?

I looked into a large battery pack generator to plug the CTEK into but based on the max voltage from the ctek at 5amps, I'd need one huge power brick costings thousands! Plus I gather it's not particularly efficient.

Really good to know that isolating the battery doesn't cause any issues if I keep disconnecting when not in use. Based on how fragile the electrics are on the car when the voltage drops I'm surprised I must say! I might also look to check there isn't a navtrack installed as when I was searching the forum to see if this had been asked before, I noticed a lot of owner have issues with drain after 5 years.
 

MarkMas

Member
Messages
3,511

Gazcw

Member
Messages
1,280
A cheap and simple way is to use an old battery to add capacity. Charge up the old battery at home, for 24 hours, and then connect it to the car's battery via jump leads. It won't upset the electronics, the battery will effectively double the capacity and you can easily remove it for another recharge.
You read my mind. Didn't take long did it!
 

Gazcw

Member
Messages
1,280
Ahhh yes, Monday morning combined with lack of caffeine = one special post... I can't believe I missed that it wasn't a battery pack haha!
Thanks for the suggestions everyone, much appreciated. I think the "old battery" method is going to be the most suitable as my parking is underground. I've seen Harry Metcalfe using the solar charger on that Sl600 he had in France which worked a treat but unfortunately won't for me :(.

I don't have an old battery but no worries buying a new one. My concern I guess would be leaving the jump leads on it unattended with the battery hanging out of the boot. Could there be a fire hazard or anything?

I looked into a large battery pack generator to plug the CTEK into but based on the max voltage from the ctek at 5amps, I'd need one huge power brick costings thousands! Plus I gather it's not particularly efficient.

Really good to know that isolating the battery doesn't cause any issues if I keep disconnecting when not in use. Based on how fragile the electrics are on the car when the voltage drops I'm surprised I must say! I might also look to check there isn't a navtrack installed as when I was searching the forum to see if this had been asked before, I noticed a lot of owner have issues with drain after 5 years.
You could put in an a battery isolator switch if you do not have one for ease instead of messing with the clamps all the time. I also have one of these as an emergency. Good for large diesels and petrol V8.

 

midlifecrisis

Moderator
Messages
8,417
Just keep it simple, battery and jump leads. Undo the covers, and mount the old battery on the side. Negative to negative, then positive to positive. Connect the leads in one decisive action and you won't get any sparks.
When you remove the battery to charge disconnect both leads from the car's battery to avoid shorts.