Wire batteries in series or parallel

[southport2014 10+ year member]

How should i wire my batteries also whats the differecne between these two and

also what are these for The Install Bay IB500 500 Amp Battery Isolator and Relay (ib-500)

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[rebelfromva 10+ year member]

Parallel.

 

[bhsdriller 10+ year member]

Parallel

 

[keep_hope_alive Premium Member]

series would destroy most of the vehicle's electronics.

batteries in series add their voltages, so two 12VDC batteries in series would be 24VDC.

batteries in parallel add their current supply capabilities while voltages remains the same.

the isolator is a large relay that opens when the car is off to disconnect the front and rear batteries. it prevents the two batteries from discharging into each other while they sit.

people also use isolators so they can park-n-play without draining the front battery down. this has an adverse effect when the two are recombined and the main battery discharges into the rear battery.

 

[maylar 10+ year member]

people also use isolators so they can park-n-play without draining the front battery down. this has an adverse effect when the two are recombined and the main battery discharges into the rear battery.

Never having used one, but being curious... could the relay be delayed until the engine is started?

 

[pro-rabbit 5,000+ posts]

series works for hydraulics //content.invisioncic.com/y282845/emoticons/fro.gif.c695f1f814b01c4ad99fe7f8cccadd29.gif

But they are right, parallel keeps everything a 12 volt system. If you series them you jump to 24 volts or higher depending on how many batteries you have.

 

[keep_hope_alive Premium Member]

Never having used one, but being curious... could the relay be delayed until the engine is started?

That is an issue, and you could build an analog delay for a specified time easily. Requiring the engine to be running is possible, but more involved in analyzing the schematics and safely adding that function. I would use a NPN transitor to isolate the relay control from the circuit you use.

 

[maylar 10+ year member]

That is an issue, and you could build an analog delay for a specified time easily. Requiring the engine to be running is possible, but more involved in analyzing the schematics and safely adding that function. I would use a NPN transitor to isolate the relay control from the circuit you use.

Seems like it aught to be a feature built in to the isolator. Wouldn't be a big deal, and it'd add marketing appeal.

In the old days we used the alternator's "idiot light" circuit or a switch on the oil pressure sensor to operate relays when we needed something switched with "engine running". Worked for electric chokes etc. Prolly more difficult with today's computerized cars.

 

[keep_hope_alive Premium Member]

adding features adds cost. no one wants to add cost.

tapping circuits now - it's all digitally controlled outputs for LEDs and you don't want to add any load to them. old days had lamps which drew a decent amount of current anyway...

 

[TDot 10+ year member]

people also use isolators so they can park-n-play without draining the front battery down. this has an adverse effect when the two are recombined and the main battery discharges into the rear battery.

Could you elaborate on this please?

 

[bhsdriller 10+ year member]

Could you elaborate on this please?

the isolator makes the one in the rear stand alone, isolates it from the front. It's not drawing anything from the front one

When you combine them again, the back battery will be resting lower then the front from the usage. The batteries will want to equal out, the back one will drain from the front till they are sitting equal

Something like that

 

[TDot 10+ year member]

Thanks, I kind of expect the back to draw from the front at start by the nature of the set up. The quetion is, why is this a problem? I would expect if it was serious there would be a ready made work around. Can something be damaged? What are adverse consequences of this? How bad can it really be? GENERALLY how long would it take for the battery to charge back up? Would a capacitor inbetween the batteries help/remedy the issue?

 

[jockhater2 10+ year member]

wire it in series. and then make a video of the smoke and damage that follows //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[TDot 10+ year member]

Great responsive help...if that actually made sense to me or resolved my questions. Anyone else care to actually answer my questions and provede a helpful response that I can actually learn from and prevent my car from smoking like the previous genious felt compelled to state...considering I'm actually here to learn something and prevent said problem(s)?

 

[keep_hope_alive Premium Member]

Paralleling batteries that are at different voltages is very hard on them. Shortens life.