Which way for small battery pack?
Submitted: Wednesday, May 09, 2007 at 16:25
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tdv
Hi all
Just trying to figure out the best option for a small battery in the camper trailer. it is only need to run lights so i'm thinking around 20amphr which should last for 20 hours of light with my setup.
Should i find one of those little
power packs or just by a 20amphr sealed battery and run the cable from the andersen plug (which runs 3 way fridge when on the move) to the battery to charge on the go???? Is this feasible? Will it run the fridge and charge a small battery at the same time? The cabling comes from my second battery under the bonnet.
Other option is to put it in the car and charge from cig lighter. I'm guessing a 20 amp battery isn't too big to fry the cabling????
cheers
terry
Reply By: Bware (Tweed Valley) - Wednesday, May 09, 2007 at 17:49
Wednesday, May 09, 2007 at 17:49
Hi Tdv,
I use one of those jumpstarter/powerpacks. I'm not running a fridge, just 12v light, AA battery charger. The advantages of these units are that they are portable (have your lighting wherever you need it), can be recharged from mains or through 12v ciggie lighter plug. You can get them with built-in torch, warning lights, even air compressors.
Regards,
Brian
AnswerID:
238842
Reply By: Mike Harding - Wednesday, May 09, 2007 at 17:59
Wednesday, May 09, 2007 at 17:59
Try one of these:
Site Link
What will your fridge run from? You may need to ensure the 20Ah doesn't "backfeed" into your main system. Do you really need an additional battery just for lighting?
Mike Harding
AnswerID:
238844
Follow Up By: joc45 - Wednesday, May 09, 2007 at 18:19
Wednesday, May 09, 2007 at 18:19
Also
check what Siomar Batteries can offer.
Sometimes the best price, certainly the best range of these sort of batteries.
(no offence, Dereck!)
Gerry
FollowupID:
499894
Follow Up By: Mike Harding - Wednesday, May 09, 2007 at 18:27
Wednesday, May 09, 2007 at 18:27
Hi Gerry
Got an Oz distributor for Siomar? Their website doesn't give one.
Mike harding
FollowupID:
499900
Follow Up By: Robin - Wednesday, May 09, 2007 at 19:08
Wednesday, May 09, 2007 at 19:08
Thats what I use mike , but wouldn't reccomend it in this case as it requires to high a charging voltage for use in Van - and would also suffer if reconnected after part discharge because more than 5 amp inrush current overheats the Gel.
I would reccomend a standard small lead acid - deep cycle if cost no object , and not an AGM
Robin Miller
FollowupID:
499908
Follow Up By: joc45 - Wednesday, May 09, 2007 at 19:37
Wednesday, May 09, 2007 at 19:37
Hi Mike,
try this:
siomar batteries
Might only be in WA, tho.
cheers,
Gerry
FollowupID:
499912
Follow Up By: Member - Oldplodder (QLD) - Wednesday, May 09, 2007 at 20:01
Wednesday, May 09, 2007 at 20:01
Mike,
Yep, have used these for a 3 or 4 years now.
Got a few years out of them.
Problem is charging.
Recommend maximum of 1.5 amps.
So i Have rigged up one of these
Site Link
as a charger off the 2nd battery in the car.
Charges when the 2nd battery is on charge as it uses 13.8 to 15v input to charge 2nd battery in car has a rotronics controller that switches over after main battery s charged.
FollowupID:
499917
Reply By: Member - Phil G (SA) - Wednesday, May 09, 2007 at 20:21
Wednesday, May 09, 2007 at 20:21
I used to run 7Ah gel cells for a
camp light - the light would only get used for a couple of hours each night - so would last a few nights easily. I made up a relay that would charge the battery only when the ignition was on - kept it nicely charged. But you can charge those gel cells too quick - I controlled the rate by using longer length of thin wire to increase the voltage drop - crude but it seemed to work.
AnswerID:
238896
Reply By: Mainey (WA) - Thursday, May 10, 2007 at 00:01
Thursday, May 10, 2007 at 00:01
Question is 'why do you need another battery' at all just to run some lights ??
Why not just use the
power from the battery that supplies the 3 way fridge
power ??
As you 'imply' the 3 way fridge uses gas of a night so it will not be drawing any 12v
power at all, and the lights will only use about 2ah x 5 hours = 10ah MAXIMUM, basically nothing at all compared to a fridge.
Will cost only the price of a bit of 6mm▫ cable and a connector, ~$20
AnswerID:
238981
Follow Up By: tdv - Thursday, May 10, 2007 at 08:48
Thursday, May 10, 2007 at 08:48
Just convienience I guess. I'd also like to be able to take it in the tinnie to run the depth sounder. My AGM under the bonnet runs a 30l 12 v fridge/freezer.
As you say it is only $20 for some cable....and i guess lights could easily be run from the starting battery anyway.
So if I got a small (say 7amp/hr) battery then....could it be charged from the cig lighter???
FollowupID:
500048
Follow Up By: Mainey (WA) - Thursday, May 10, 2007 at 22:45
Thursday, May 10, 2007 at 22:45
question is would it run the depth sounder... I don't know the answer, probably will.
BUT, I would not expect a "cigarette lighter" to recharge a battery of any size, I would use a dedicated larger capacity fused cable than those often used by cigarette lighters.
FollowupID:
500219