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Discussion Starter #1
As far as I know, the battery in a car is only needed to start the engine. Once the engine starts, the power needed to run the radio, speakers, and all fancy electrical components, are all powered by the alternator.

To me it seems if one needs more power (due to added equipments that need more power), one needs a better alternator.

Could someone tell me what's going on?
 

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Think of all the power your rig uses as a river.

The river is fed by a lake (battery), so naturally if your river gets big enough, the lake will dry up.

Your alternator is like another river, which feeds the lake. Your alternator works when the engine is running, so your lake can only fill at those times.

Lights, stereos and stuff that you generally use only when the rig is on would benefit from a larger alternator, as the lake wouldn't need to be used as much.

Winches (which pull more power than any alternator can possibly supply) benefit from a larger lake (battery). This goes for anything that you plan to use while the engine is off too.
 

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I agree with 2010army green, winching will discharge the battery faster than the alternator can recharge it (if use is prolonged) and a fridge for a few days can drain enough battery to keep it from starting. Getting a jump start in the woods can prove difficult! Plus, it's cool.
 

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If you are out somewhere and your battery fails, you're done. If you have dual batteries you can use the second battery to get you back to where you are going. I had to use mine this way for a few days until I could replace my main battery that died.
 

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No. But, using a winch will drain your OEM battery pretty quick.

I use a single PM-1 battery and carry a Jump N Carry. I didnt want to deal with 2 batteries.

Is second battery mandatory if you plan on using a winch?
 

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Another reason is you can use a second battery as a backup. You'd have your "primary" battery, that does all the work under normal conditions and a "auxiliary" battery that is just maintained.

If for some reason your primary battery dies, you can switch over to your aux and still start your engine.
 

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Another reason is you can use a second battery as a backup. You'd have your "primary" battery, that does all the work under normal conditions and a "auxiliary" battery that is just maintained.

If for some reason your primary battery dies, you can switch over to your aux and still start your engine.
^^^^^^ this

already self-boosted once :)

makes you wonder why all cars don't come with a 2nd battery?!
 

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To impress your neighbors when your brand new Sears Platinum battery fails. Jump start it with a flip of a switch with the 2 year old Odyssey. Who ever claims they are the same- needs to have both to appreciate how much they aren't.
 

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Type of battery is also important.

If you plan on winching alot with the car turned off, standard plate style batteries are not designed for deep cycle usage. Getting a good sealed battery like an optima battery, marine battery, or a performance audio battery allows you to actually drain the battery without causing damage to it.

Still, I don't like the idea of adding greater amperage draw to a vehicle without first beefing up the alternator. Seems to me that if you plan on adding electrical accessories that have substantial amperage draw, that you should at least get the supporting modifications to allow it to do its job correctly without fear of being stranded somewhere.
 

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Type of battery is also important.

If you plan on winching alot with the car turned off, standard plate style batteries are not designed for deep cycle usage. Getting a good sealed battery like an optima battery, marine battery, or a performance audio battery allows you to actually drain the battery without causing damage to it.

Still, I don't like the idea of adding greater amperage draw to a vehicle without first beefing up the alternator. Seems to me that if you plan on adding electrical accessories that have substantial amperage draw, that you should at least get the supporting modifications to allow it to do its job correctly without fear of being stranded somewhere.
There in lies one of the issues- there arent any decent worth while upgrades to our alternator. Ive been waiting for Mean Green to finally come out with one but I guess this will take forever.

As stated above- many of us like to camp with the FJ and run things like ARB fridges and such. This draws power at night while the vehicle sits. Both of my batteries are AGM style sealed batteries which are better suited for off road since they can work a=in any orientation and dont leak.
 

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Hey everyone!

I'll be having an ARB bumper (with the Warn winch) installed, and I was wondering if I could get away with my Toyota (OEM I assume?) battery. I won't be winching very often, but if/when I do, will the battery suffice? This is the one I have.

I also run a BlackVue DR500 dashcam with the power magic pro, and Toyota's OEM aux lamps (55 watt).
 

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I did some winching with my OEM. It will last a few winchings. Dont let it draw down the battery too much while winching.

After two winchings my battery only charged to 75% after that. So, your OEM will eventually die with lots more winching. I just put a battery monitor in the dash so I can see how useful the OEM was. When it got low enough i switched to a deep cycle AGM battery as my main battery.

Hey everyone!

I'll be having an ARB bumper (with the Warn winch) installed, and I was wondering if I could get away with my Toyota (OEM I assume?) battery. I won't be winching very often, but if/when I do, will the battery suffice? This is the one I have.

I also run a BlackVue DR500 dashcam with the power magic pro, and Toyota's OEM aux lamps (55 watt).
 

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I did some winching with my OEM. It will last a few winchings. Dont let it draw down the battery too much while winching.

After two winchings my battery only charged to 75% after that. So, your OEM will eventually die with lots more winching. I just put a battery monitor in the dash so I can see how useful the OEM was. When it got low enough i switched to a deep cycle AGM battery as my main battery.
So, a deep cycle battery would be a more practical route to go, I take it?
 

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Hey everyone!

I'll be having an ARB bumper (with the Warn winch) installed, and I was wondering if I could get away with my Toyota (OEM I assume?) battery. I won't be winching very often, but if/when I do, will the battery suffice? This is the one I have.

I also run a BlackVue DR500 dashcam with the power magic pro, and Toyota's OEM aux lamps (55 watt).
The factory Panasonic is a great battery to begin with. I only got rid of mine due to it draining out all the time while I was away (2-3 months)
 

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There in lies one of the issues- there arent any decent worth while upgrades to our alternator. Ive been waiting for Mean Green to finally come out with one but I guess this will take forever.

As stated above- many of us like to camp with the FJ and run things like ARB fridges and such. This draws power at night while the vehicle sits. Both of my batteries are AGM style sealed batteries which are better suited for off road since they can work a=in any orientation and dont leak.
I know a guy who builds custom alternators. Had one made for my celica. Upgraded from an 80A to a 180A and it ran about $450 including a red powdercoat. You can either send your old one in and have him make it, or he will go and buy one and retrofit the guts.

Here's a link (turn your sound down/off): LINK

And here is my alt he did for me:



If he can do it for a car that they sold 300 of in North America that year, im certain he can tackle a more common vehicle...
 
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