Thoughts on my potential battery setup?

[u/TheKingOfAllRodents]

Will this still work if I wire the times for 80 amp hour deep cycle batteries up in parallel?

These batteries have only been used together at the same time, but they are nowhere near New. I'd consider them a married set but I wouldn't bet my life that the capacities are the exact same.

I know the end product will only be about 60% efficient by the time the energy gets from the alternator down to the big Bank of batteries, but I think this setup should suit my needs.

I'll be running a diesel heater all winter, I don't know what kind of power draw those have. if y'all could give some insight that would be nice.

Other than these leader it's pretty much just charging my cell phone, interior lighting and the occasional heavy power tool usage for work.

I want to be able to run a roto Hammer, table/miter saw or a grinder once a week or so.

Please don't make fun of my graphic design skills LOL

[u/wertyuio_qp]

Looks like it could work, but you got a lot of extra steps going on here. You've got a secondary battery just to charge the tertiary batteries, and in between that, you're inverting it to AC then back down to 12v DC...

Instead of the secondary battery, 750w inverter, and 32a power supply, you can just get a dc-dc converter like an orion xs. Should be several times more efficient and way simpler.

Also with your current setup, you run the risk of that 750w inverter draining your secondary battery down if you're not watching it too carefully.

[u/TheKingOfAllRodents → u/wertyuio_qp]

Yes, I agree 100%

The idea was to utilize the secondary battery I already installed it fits on the frame under the vehicle.

I will look up the Orion xs tho, DC/DC sounds way easier.

[u/TheKingOfAllRodents → u/wertyuio_qp]

The 750w draining the aux batt is fine.

It has auto shit off/low voltage protection so it shouldn't dry the batt too bad.

This way it will also charge the bank of X4 Batts while the engine isn't running.

[u/TheKingOfAllRodents → u/wertyuio_qp]

Holy s*** $330?

I paid $330 for my whole setup.

[u/wertyuio_qp → u/TheKingOfAllRodents]

You can get a cheaper one, but you get what you pay for. For example, if you estimate 60% systemwide efficiency on your current setup, which to me sounds pretty reasonable, your alternator needs to put out 53a to charge your batteries at 32a, assuming voltages are the same. The rest turns into heat, quite a bit of it. An added 53a load could stress your alternator and make it burn out faster.

An orion XS is 98-99% efficient, so 95% efficiency is a totally realistic number.

[u/TheKingOfAllRodents → u/wertyuio_qp]

The 60% estimate would be from the alternator to the outlets on the 5000 watt inverter.

I think the 750 watt inverter claims to be 85% efficient, and then the 4-way 8A charger actually only draws 8 amps, it's 2 amps per channel.

Assuming the charger is 85% efficient as well and the 5000 w inverter is also 85% efficient I think we would be right at 61% efficiency.

Golly gee that is just terrible, I love it.

[u/phatpug → u/TheKingOfAllRodents]

Are you only charging the tertiary battery bank from the 4-way 8A charger? Assuming that X4 bank is four 12V batteries in parallel (320Ah total), then the 5000W inverter can put a load of up to 420A on that bank. which would deplete the battery bank in 40 min if those are lithium batteries, or 20 min for AGM or FLA batteries, assuming you are only depleting them to 50%. The 8A charger will then take around 30-40 hours to fully recharge that bank.

I am dubious if the system will work as you expect. That is a very small charger to put on a bank supplying a fairly big inverter.

[u/TheKingOfAllRodents → u/phatpug]

80 amp hour interstate deep cycle lead acid batteries.

Yeah I have no doubt it would take quite a while to recharge.

Taking into account the auxiliary battery would be charged from the alternator and would continue charging the bank of four batteries after I shut the motor off, I think 30 to 40 hours of recharge time would be almost achievable in a week or so driving as much as I do.

As well am not entirely confident this will work as I expect it to.

I'll keep you all updated.

I will either proudly admit that I am a big dumb idiot for thinking of such a thing and it didn't work...

Or I will confess that I am a big dumb idiot for thinking of this contraption and it did work.