Dual Batteries for dummies

[xychix]

would this be usable:

http://www.banggood.com/12V-200A-Heavy- ... 16572.html

At only 8 euro's it can't be much....

[martynvella]

would this be usable:

http://www.banggood.com/12V-200A-Heavy- ... 16572.html

At only 8 euro's it can't be much....

Look at it from another angle, where are you going to be and what will it cost you if it fails?

After having said that, even a top quality one can have faults.

How much does the Bosch equivalent cost, the difference wouldn't be much more than the steak that you lose when your fridge goes hot.

[xychix]

would this be usable:

http://www.banggood.com/12V-200A-Heavy- ... 16572.html

At only 8 euro's it can't be much....

Look at it from another angle, where are you going to be and what will it cost you if it fails?

After having said that, even a top quality one can have faults.

How much does the Bosch equivalent cost, the difference wouldn't be much more than the steak that you lose when your fridge goes hot.

Yeah I've ordered one.

WORST case it shorts the + HIGH AMP to ground (which is there on the thinner switching side).
Therefore I'll fuse the thick cable 200A near battery and fuse the groundwire from the relay to ground with a 5A fuse.

As the relay has 4 legs that can be 12V there's only one disasterwire... the ground wire : )

[TOYZX]

A question for anyone running an auxiliary battery in the rear of their rig. Do any of yas have it rigged for a backup starter? If so have you fused your large wire goin from front to back?

[xychix]

A question for anyone running an auxiliary battery in the rear of their rig. Do any of yas have it rigged for a backup starter? If so have you fused your large wire goin from front to back?

I would always fuse this wire and if needed have a manual override (eg a thick wire bridge over the fuse that can be installed manually..)

just a personal preference

[TOYZX]

Yeah was planning on fusing it but beind such a long and large wire witb a power source at each end should i be fusing each end? I was thinking about a 100amp anl at each end?

[martynvella]

If you are intent on fusing it, then yes a fuse at both ends, and id go for fuses a bit higher than 100 amp, you wont get much cranking speed with a diesel for one hundred amps, the starter with no load would draw 50.

The fuses will protect against a sudden hard short, but if it is a gradual rub through there will be the potential for a hell of a lot of heat to be generated before the fuses blow.

Not many cars have fuses on the starter cable, well none that I know of.

Probably better spending the money the fuses and holders would have cost on better insulation and protection of the cable itself, or an isolator at each end that only gets turned on if you need to start through it.

And check with the supplier of whatever dc dc charger you are running to make sure you can short the input to the output without damaging it.

[TOYZX]

Im only going to be running a isolator up front as my alternator pumps 14v all day. So a fues at each end and good insulation. Fuse recommendation?

[martynvella]

get a sparkie to put a clamp meter on your starter cable and get the peak current reading and go 50% higher. I have never done it on a hilux and my clamp meter is on what looks like perminant loan.

[TOYZX]

Yeah know that feeling with tools! Ok cheers!

[Jacko9]

I ended up following a different strategy. At the moment, I am not doing a heap of driving whilst at uni, but still have my fridge permanently on the back, so I think a DC-DC charger would struggle to deliver the kind of power it needs in the short period of time I drive unfortunately. So I've gone with a Redarc VSR, Optima D27, and a voltage booster from ABR, I am hoping this will suit my current situation. If it doesn't, it was worth a try and I will still use the old VSR and replace it with a DCDC, it will be interesting! I am halfway through the install now, will update in a few weeks.

[martynvella]

Its all a compromise and the trick is to derive a set up that works for your current situation, which you have done theoretically.

An AGM battery is capable of taking a higher charge rate, however it is not recommended. The higher the current flow in either direction has an affect on the battery life time, not to mention the alternator struggling at high outputs.

It may be much more cost effective to take your lunch to uni in a lunch pack with a couple of ice bricks and leave the fridge turned off.

My fridge is permanently in the back too, but I only turn it on when I need it. Every cycle the battery does is one cycle closer to the end of its life.

[Jacko9]

Definitely mate, and i agree its a compromise.

Regardless of whether I had the fridge off at uni, it would be the same issue with my job now too, which is earthmoving, ute spends most of the time still, and I am just staying in huts where we are working. I will just see if it works, if not the VSR can go to the old workute, as we run a fridge on that for cattle and sheep vaccinations.

Whether I have got it all right, I don't know, maybe not, but maybe I have! its something that interests me so I am happy to fiddle around.

Definitely taking your advice onboard though mate, It is smarter for me to leave the fridge off when at uni, so I will do that!

Cheers.

[fracturedranga]

Is there any reason you can't mount a solar panel on the roof and run it through a dc dc charger with a changeover relay? Then when your car is sitting around it'll still be charging.

[TOYZX]

Thats how redarc do it ranga. Am doin systems like that at work all the time.

[fracturedranga]

Yeah that's why I mentioned it, I'm about to set up my redarc the same way with a permanent mounted 100w panel

[Richolux150]

Thats a pretty big disclaimer attached to the ADB........(voltage booster)

[Jacko9]

I did think about a Solar Panel with the BCDC unit, but to be honest, I don't want to put a solar panel on my ute, I am a bit unsure of where I actually would put it, I don't really want it on the roof as I am putting a rack on top, and I have a tray back. As said, if this solution doesn't work, I will just go to a bcdc charger, but I am more than happy to give this a go first.

[sharp018]

Just a quick question

My missis has got a 120 Prado
The battery is a genuine n70zzL toyota battery

Which i believe has been in the car since day dot 2008

We went camping this weekend just gone, and just by having the car off and the doors open with the interior lights on for a bit. The battery went flat


I come home sus it all out find the water level is low i top it up with distilled water and plug it onto my AC to DC charger at 12v slow charge

I let it go over night, next morning i unplug and check it after an hour as the voltage was reading 13.14v it eventually went down to 12.91v and staied there

I know for a fact this battery is no good for a starting battery as it just doesnt have the power. But ive connected a 300w invertor and my led florescent light and had it for for 30 minutes, with volt meter connected aame time. The voltage level was dropping from 12.91 down to around 12.55 really quick, but after that would take a minute or 2 to go lowwer. When i turned it off the voltage would come back up. Its not sitting on 12.76v

But even after direct charge over night the little eye bubble indicator said it needed charging even though it was on 12.91v


Sorry about all the writing

Question is:

Can i use this battery as a dual to run like led light bars and cb radio, in theory the car will be constantly running so the alternator will keep charge to the battery therefore wont go flat

The only time it could is if she was to turn the car off and use it but who does that anyway . Or for a long period of time.



I dont really have the funds to buy a dual battery for her as i jusr replaced this one.

Which is why im asking

But same time if it telling me it needs to be recharged and ive had it on all night and its showing 12.91v would having it constantly charge over charge it like running from alternator? Ive had a battery before in my lux that went that bad it smelt like rotten eggs as all the "hydroden"? From the battery leaks out or vaporizers

If this is the case ill chuck it away

[Alby]

I would leave it on charge for longer than that and do it with a multi stage charger if you have one

What is the purpose of having it all connected up to run your radio and led bar? Your cranking battery will easily handle that