Do I need a 2nd battery? (Already have HO/Big3)

[CannedDog]

Current Specs

2001 330i
U12 (Adding a 2nd very soon)
Singer 320 AMP
SIA - 3500
O Gauge all round

Since I plan on adding a 2nd U12 and wiring it down to 1 ohm I am worried that I will be drawing to much from one battery. My voltage is at the moment stable. I don't know if this would be a legitimate issue or not.

Click to read more...

 

[Dafaseles]

I would run a second battery. If you can get 2 80 ah AGM batteries, that should keep your voltage solid. You could probably get away with a little less amp hours though, I don't what options you have for a stock sized battery replacement.

 

[CannedDog]

I would run a second battery. If you can get 2 80 ah AGM batteries, that should keep your voltage solid. You could probably get away with a little less amp hours though, I don't what options you have for a stock sized battery replacement.

I believe the biggest stock battery I can fit is an H8. Room in the trunk isn't an issue right now (yet), so I can pretty much go with anything.

 

[Dafaseles]

I believe the biggest stock battery I can fit is an H8. Room in the trunk isn't an issue right now (yet), so I can pretty much go with anything.

If it where me (and granted I prefer to go a little overboard) if you can get 100-125 amp hours out of some good AGM batteries, I don't think you'd have any problems.

 

[Bobbytwonames 5,000+ posts]

Current Specs

2001 330i
U12 (Adding a 2nd very soon)
Singer 320 AMP
SIA - 3500
O Gauge all round

Since I plan on adding a 2nd U12 and wiring it down to 1 ohm I am worried that I will be drawing to much from one battery. My voltage is at the moment stable. I don't know if this would be a legitimate issue or not.

One bank of lithium in the trunk. Less weight, smaller, cheaper, better, and lasts longer.

 

[CannedDog]

One bank of lithium in the trunk. Less weight, smaller, cheaper, better, and lasts longer.

View attachment 31462

Do you have any recommendations for brands for Lithium batteries?

 

[Bobbytwonames 5,000+ posts]

Do you have any recommendations for brands for Lithium batteries?

Lishen or Yinlong seem to be the popular ones. XS Power also.

 

[Firewalker]

@hispls has a ton of experience with Lithium from what I can remember. I would also be asking him hopefully he will pop in.

 

[Bobbytwonames 5,000+ posts]

Do you have any recommendations for brands for Lithium batteries?

I also run an SIA3500 with a mechman 320, AGM, 1/0 Big 3, and one bank of Lishen lithium. My voltage used to drop pretty low (high 11's) until I added the lithium. @Popwarhomie knows a lot about lithium as well.