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Discussion Starter #1
I have another problem for battery's for semi trucks. I would like to switch from the 4 lead batteries in the semi tractor to running enough Lithium batteries to run my heater or A/C while parked but not idling. More and more states are really hitting truckers hard for idling. I would like to run 2 1500 watt invertors for say 10 hours. If I could pack enough batteries in the truck battery compartment for a full 34 or 48 hours without starting truck that would be better but lets start with just enough for 10 hours. I would also need to charge these battery's off of the original charger system on truck. Hopefully this will be easy enough to put into the original battery box. The Charging system is 12 volt and is capable of 180 amps I believe. I am planning on buying another truck and want this setup in the next truck I buy. Battery box size will be in next post if that is needed. Thanks
 

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Uhh, that's very large battery pack. 10 hours @ 3000W is 30kWh (30,000 watts) of storage. About $12,000 in LiFePO4 money. And the pack would weigh around 700 lbs.

If you went with a more energy dense lithium it would be about 30% lighter, but cost twice as much.

Of course, you should do an audit to see just how much energy you actually use in that 10 hour period. Running the inverters is easy. Running them at full load for the entire 10 hours... not so easy.

Keep in mind, that amount of energy is almost equivalent to a gallon of petrol. And in the EV world gives most conversions a range of around 75-125 miles.

Oh, and add 10-30% on top of all that for pack longevity.
 

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Discussion Starter #4
I looked at the apu units for trucks. They are deisel generators designed for trucks. But those are $6,000 to $15,000 for one. Not sure if that is the installed price or just for the unit. The more expensive the more it can do. Obviously the cheap one doesn't do much. But then I guess I wanted the Battery's to just save deisel fuel anyway. Currently the truck I use goes thru about 1 to 2 gallons of deisel at idle per hour. So that is way too expensive for my taste. luckily I am not the one paying for the fuel. Well I will just keep looking for a truck with an apu unit and wabasco heater already on it. Thanks guys for replies.
 

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Discussion Starter #5
O didn't read the rest of your post their overlander hehe. just saw the 12,000 for the batteries. here's a list of what I have running on the inverters.

Cell phone charger.
bluetooth charger.
2 Laptops 1 is 90 watt power supply other is 200 watt power supply.
router.
verizon mifi 2200.
speakers for laptops.

So not much, But since I already own 2 1500 watt inverters I want to stick them both in the truck. Currently if I just use my 90 watt laptop I can almost put everything else on a 450 watt inverter. but I don't like to use multisocket extensions in the truck. The apu units are rated for about 1 gallon per 8 hours of normal use. But I ain't normal. never ever ever gonna claim to be. rofl.
 

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There's a big difference between using 3000 watts an hour or 450 watts an hour. If you only need 450 watts an hour for 10 hours (you can still use the two 1500w inverters, but only draw 450 watts from them) then the price for the battery pack would fall to around $2,000.
 

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Discussion Starter #7
I think I found a diesel generator for 470 bucks on ebay that I will modify to sit behind cab. Now I just need a heater and A/C setup for it and I am good to go. But it would have been nicer to have battery packs instead. but alas I will have to wait a few more decades.... Thanks guys for the help.
 

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$470 + fuel vs ~$2000 in batteries...

If the APU uses 0.5 gallon of fuel an hour (wild guess), then over a year (10 hours a day, 5 days a week, 52 weeks a year), you're going to be spending $1300 in fuel. Compare that to $2000 for some LiFePO4 batteries that might last ten years or more if you treat them gently and it's a no-brainer. In the first year the batteries will have nearly paid themselves off. Reckon Diesel prices are going to come down soon?
 

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$470 + fuel vs ~$2000 in batteries...

If the APU uses 0.5 gallon of fuel an hour (wild guess), then over a year (10 hours a day, 5 days a week, 52 weeks a year), you're going to be spending $1300 in fuel. Compare that to $2000 for some LiFePO4 batteries that might last ten years or more if you treat them gently and it's a no-brainer. In the first year the batteries will have nearly paid themselves off. Reckon Diesel prices are going to come down soon?
I thought of that too when he posted but problem is he won't be charging those batteries from an outlet, he'll be charging them from the truck's alternator which will waste as much if not more diesel than the generator. Definately worth it if you're charging at 15 cents a KW, not if you're charging from a generator to begin with.
 

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I hate to suggest it, but get a Honda 1000 or 2000 generator. They are quiet, effecient and have your inverter already in.
 

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Discussion Starter #11
Well I would have been charging from the truck altenator over a 10 or 11 hour driving day. I would have liked that to be possible anyway. The Diesel generator was a second option for running accessories and to keep warm or cool, instead of just straight battery power while I wasn't driving. The Whole Idea is to stay comfortable and still use my accessories without actually running my truck engine which burns about 1 to 2 gallons of diesel an hour at idle. The APU or Auxiliary Power Unit costs $5300 to $10,000 without installation. The Battery Pack Option will also cost $2000 to $12,000 without installation. I was just hoping not to have to spend money to idle but didn't have the up front money needed to get an apu or battery pack unfortunately. I would rather not have the generator to run while sleeping for comfort and accessories but on the cheap side that might be my temporary option at the moment. The apu's are generally rated for about 1 gallon per 8 hour day of use and is tied directly to the radiator and fuel tanks of the truck. I like that but it costs about 100 bucks an hour for install and usually takes about 8 hours to install. O and I am mostly deaf thanks to semi trucks lack of noise dampening materials. I wouldn't hear a freight train out side my truck if I am sleeping lol.
 
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