6 Volt positive ground battery upgrade to Lithium Ion.

[53Murf]

Has anyone attempted to replace their lead acid cell 6v battery with a lithium Ion? I have a 1953 Dodge B4C that I haven't driven in 8+ years and since I'm guessing the battery is trash I would try to use 4 lithium batteries as shown  I'm sure i can adjust the regulator to 7.2 V DC output but I don't even think I need to deviate from the stock settings.   Got these "Grade A 4PCS 3.2V 280AH Battery LiFePO4 Lithium iron phosphate Battery Packs" for 225.00 bucks And will let you all know how it works out. 

Please let me know if anyone thinks this is a bad idea or have any recommendations.

Thanks

Murf

 

Battery specs

Specifications

product Name: Lithium iron phosphate cell.

Shell Material:Aluminum.

Rated capacity:280Ah.

Minimum capacity:280Ah.

Internal impedance:0.1~0.3mO.

Nominal voltage:3.2V.

Dimensions(L*W*H):174*72*205mm.

Weight:5.22±0.2kg.

Recommend Constant Current:280A(1C).

End-of-Discharge Voltage:2.5V.

Recommend Constant Current:140A(0.5C).

Charge Voltage:3.65V.

Max Continuous Discharge Current:280A(1C).

Cycle life (80%DOD):4000 cycles.
 

Edited May 1, 2021 by 53Murf
Specs

[maok]

You will need a charge regulator, and a BMS for the individual cells.

 

Best to stick with lead acid. 

Edited May 1, 2021 by maok

[53Murf]

Thanks Maok!

I was thinking about the BMS but I couldn't find one for 6V only 12 and 24v .  I was hoping the original regulator could do the job if I balanced the voltage out before I installed them and just used a simple monitor to show if the voltage gets out of balance then retune them.

I think you are correct I will need to try to find a BMS for the 6V layout. Since I bought the batteries already I hope its not total waste since I may be able to use them in my electric lawnmower maybe?. 

Thanks again

Murf

[maok]

Also, you don't have enough cells, that's only 14Ah, you need more capacity for it to not stress the cells. 

[53Murf]

Hi Maok,

I didn't even think of that at all. I always make assumptions and should have asked the question earlier.  I really liked the idea of not needing to babysit the led acid battery and have the problem of the leaking acid in the box. But I'm stubborn and will give it a try even if I need to buy 2 more batteries if you think it would be enough AH.

I just would like to share if we make this successful retrofit. It is so hard to find information about replacing lead acid batteries with Lithium since most cars now use an alternator.  

  Thank you so much even though I didn't want to hear the bad news.

Murf

[chrysler1941]

Also you need a true DC charger with electronic heat limiter protection. Your car charger mechanical regulator produces rippled DC, and has only a primitive mechanical current limiter and will produce destructive spikes. If you want to get rid of acid battery, go AGM.

Edited May 1, 2021 by chrysler1941

[maok]

There are packaged Li car batteries available, well here in australia anyway, but all 12volts not 6v.

 

2 extra won't cut it either, you probably will need 30-50Ah of capacity, so the cost won't be worth the experiment.

[Jeff Balazs]

I use a 6 V Optima battery and have never had an issue. One of my buddies just started his hot rod with an 8 year old Optima. Started right up. They last.

Hth, Jeff

[chrysler1941]

2 hours ago, Jeff Balazs said:

I use a 6 V Optima battery and have never had an issue. One of my buddies just started his hot rod with an 8 year old Optima. Started right up. They last.

Hth, Jeff

Optima are fantastic but ugly. ? Have one in my other car.

Just don't leave them discharged for long. They collapse and can't be restored. Don't ask me how I know 

[53Murf]

Thanks for all your help gents.

Looks as if I will be installing these Lithium Ion batteries in my electric lawn mower. ?

I like the Optima since I don't care what it looks like under the floor board so that works for me. And 800 CCA!! I believe the interstate Battery I used for years is only 650 CCA and never had a problem starting the old Dog so I'm sure the 53 Murf B4C will love it. 

[Desotodav]

I’ve run a 6v Optima battery in my 52 truck since 2011 and have never really had any issues. It has gone flat between drives a couple of times, which I was told was bad for them. I trickle charge the battery now and it has not let me down since. They are expensive here in Oz, but I believe that they are well-priced in USA (I was told

that they moved the manufacturing to

Mexico some years ago).

[Desotodav]

Well, it finally happened… my 11 year old 6v red-top Optima battery is dead. Trying to find one here in Oz is a challenge at present. Hopefully I will have one within the next week. Cost is about $380. The fella reckons I did well to get 11 years out of

it.

[wallytoo]

i used to be a fan of optimas, but the quality suffered in the last 6 years.  the batteries seem to fail at 3 to 5 years now, vs the 10+ i got with two earlier optimas (same exact batttery).

 

i’ve switched to a duracell agm, but i won’t know about longevity until it fails, or lasts for at least 5 years.

 

 

edit: the first optima red top i bought, back in 2004 or so, i used in my cj5 for 9 years, then placed it in my 4runner when i took the cj off the road in 2013.  it went another 3 years and finally died.  i replaced it with another red top, which promptly failed in less than 4 years.

Edited August 5, 2022 by wallytoo

[Pete]

I agree with Wallytoo. I've had two Optima 6 volt batteries. Both went bad. One because a mechanic hooked the battery cables backwards, another because the battery was apparently drained and charged too many times. In the second case I followed the charging instructions on the Optima website to bring it back, but it didn't matter. These situations have never happened with a lead acid battery in my experience, so I'm done with Optimas after two expensive lessons. I've read that their quality really suffered when they moved production to Mexico.

 

Pete

 

Edited August 4, 2022 by Pete