I have been contemplating a better way to have enough available power to give me a better margin of safety when running my extra lighting. I have 4x100w Hella 500's on top and 2x55w rear lights. This can put quite a drain on the 136amp-single battery system. I may eventually add a winch at some point as well.

When they are all on, everything currently lights without noticeably dimming the system, but I know it is a strain on the stock electrical system.

The question I have is; what would be better at providing the power needed when the lights are on...this would be in addition to the standard headlights and foglights.

Would it be better to have a dual battery setup or the 160 alternator?

John
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Larger alternator. Once the engine is started, the battery's work is done. Now if you were spending a lot of time with the engine off, but the lights on, then the dual battery would be the place to go.

Well you could start out with the 160 amp altenator,but in due time you'll need a battery with a larger "Duty Cycle".Most people think that cold cranking amps are the most important,but in my experience the duty cycle of a battery is.If you have an engine with high compression where it needs alot of cranking amps,then thats fine,but in your case you need something that will store alot of energy,and something to produce it as well.The big Altenator is a must for large current draws,but will soon take it's toll on a stock battery.I'm not sure running two batteries is the answer,however;running one good one with a high storage rating(duty cycle) is..... I can only hope this won't start a pi$$in' match.

Ron

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You are right,a good battery is a key part.I run a Optima yellow top,it has less CCA than a red top but it's amp rate and reserve minuates are greater.Also the yellow top is designed for high draw situations without hurting the battery.

I'd also reccomend a better single battery first.

I put an Optima Yellow 34/78 in mine with a total of 900w of lighting and it did make a huge difference.

With all the lights on and the Viair compressor running while the jeep is moving, I don't drop below 13.8v.

My stock battery used to drop to almost 12v

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Also check out the Odyssey PC1500 DT. It's an SAE Group 34/78 like the Optima Yellow Top, but has 825 CCA and 125 minutes reserve capacity.

http://www.odysseybatteries.com/index.htm

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in order to change the alternator to a 160 do you have to chng. anything else electrical? I was told you had to ???

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Your pulling 42.5 amps with all the lights on not cutting headlights, etc.
A winch pulls 280 to 342 amps on average, (4.5 to 5.5 hp motors) I'd go with more batteries.

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Think of your battery as a storage tank, the larger the tank the more reserve you have. A single Large Battery is good, 2 large better. But you should also upgrade the alternator so that you dont end up with 2 large dead batteries. keep in mind that when your alternator kicks on you loose power that could go to the road so the less you make it kick on and the less time its on the better.

It sounds like at some point I may want to do both.

I'll have to look into a good isolator and the alternator at some point. THe 160 amp alternator is a stock item on the renegade. All I would have to do for that is to buy a second one from the auto parts store. They run $130-160.

A good isolator runs around $100. This one sounds like a good trade off between a heavy duty diode isolator and a cutoff switch. Some good 4x4 reviews at the bottom too.

Hellroading Battery Isolator

John
];')

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I'd do the alternator & upgrade the one battery, & see where that gets you. the alternator is the bigger piece of the puzzle here. Theoretically, once the engine is started, the battery just recharges. It is only drawn from when the electrical demand exceeds what the alternator can produce. I agree that a better battery is a good purchase, but the solution to your concern lies in the alternator.

P.S. clowns never creeped me out, until I saw that one

I'd go for the alternator first and the battery second. There's no point in straining a brand new battery. Although, if there'll be a lot of current draw while the engine's off, I'd go for the battery first.

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Is it possible to find a location for a second battery under the hood? Any suggestions? Thanks!

Installing an aftermarket intake might free enough room to allow another battery to be installed in the engine area. I think the only other practical option is the trunk.

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Sorry to hijack but I have always wondered about this. So if you have a stock altenator which is what, 120amps?, and you are pulling more than the alternator is producing with engine on, does the system then ALSO pull from the battery? I wondered this b/c my truck battery used to die all the time when I would run my off-road lights even while driving; until I upgraded to an Optima Yellow Top that is.

Batteries don't make power, they store it for later use. We know that, of course, but rarely think about it. The alternator however produces electrical energy. You need a power source that is capable of producing enough power to run all the electrical stuff in your vehicle, including recharging the battery. The battery supplies the electricity when the alternator can't, like when the engine is off or when the electrical draw exceeds the output of the alternator.

It's like money. the alternator is your job & its electrical output is your income. If your running everything right, your expenses (electrical draw) is less than your income, allowing you to put what money you have left over into a savings account (Your battery). If you decide to take on another expense that causes your total expenses to exceed your income (turning on the lights), then you will have to start taking money out of the savings account to make up the difference. If your savings are shallow (old battery) then you will run out of money fast. If your savings are deep (Yellow Top), It will take longer to run out of money, but if your expenses continue to exceed your income, you WILL eventually go broke! You need to either pare down the expenses (keep the lights off), or get a better job (bigger alternator).

Your old battery may have been bad, or your alternator may be producing less than it should. I'd have the alternator output tested.

Would it be possible to modify the battery tray on the CRD to hold two batteries? What if you turned the battery sideways? Would that work? Thanks!

StarDreamer,
You have the CRD, lift the hood with a tape measure in your hand and you'll have the answer in a few minutes. The tray's an easy thing to come up with.
JTaylor,
The alternator and the battery are attached to common wires in the rig. In essence, if the electrical system was piping,the battery is a supply tank of energy under pressure. The alternator, when it's running, supplies a higher pressure. When the battery and the alternator are at the same pressure the tank/battery is full and nothing flows in or out of it, the alternator supplies the pressure and energy needed in the system through their common lines. If for some reason the alternator can't supply enough energy, than the battery supplies it, either by itself, or together with the alternator's assistance.

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I didn't realize that the Renegade had a different alternator. I wonder if that is because Renegades came with the light bar that I have now. I think I may have to upgrade my alternator and/or battery in the near future. I've already had one battery die on me but thankfully it was replaced under warrantee. I plan to add quite a bit of other electrical accessories in the future so I knew, on some level, I was going to have to do this but I never really looked into it. I plan to add foglights, driving lights, reverse lights, ARB compressor, power inverter, and up-grade the stereo

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Pete,

The HUD, Nightvision, and targeting tracking systems are cool but.......

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