Battery conversion from lithium to lead acid

[BBBHC]

The nature of forums is to get information and opinions.

[nickdalzell1]

Given the OP's response it seems he/she is just as concerned about the hazards and decided to avoid any risk and convert the car to what the OP finds more comfortable. Yet, all we are doing is debating keeping Lithiums regardless of the dangers, regardless of the OP's concerns. Why not instead help convert his/her car to lead acid as they originally asked?

I have no clue how it is setup on Lithium (cars here are always 10 years old or older) so i am not able to help myself, as i have no clue how much circuitry there is to monitor the balance of cells, temperature, diagnostics or the like. I always expect they will have far more electronics to ensure they don't explode in a fiery mess (but like the Note 7 and various RCA tablets, it's not perfect) compared with lead acid, where only the speed controller exists.

[Steve390Gold]

Originally Posted by hyper1

I am with you, don't want to take the chance.

There is no "chance" to be taken with the proper chemistry Lithium battery. See below.

Originally Posted by nickdalzell1

I know i'd want to swap them for lead acid too so give the OP a break! Lithium batteries are bad about exploding quite dramatically if abused/inbalanced (see also: Boeing DreamLiner, Hoverboard fires, Craigslist Teslas)

negative and here is why :)

You are thinking about litihum batteries that contain cobalt. THOSE are the ones to watch - the only thing a single 18650 LiCoNi needs to light off is heat. (Just over 300*F to achieve thermal runaway.) From what I've found, "abuse" that causes them to light off is either giving them a direct short to ground, or heating them to above 300*F. That is it.

Lithium used in every hybrid and every electric car do NOT contain Cobalt (Co) for this exact reason. You CANT get a leaf cell to burn, explode, etc.

Furthermore, every cordless drill battery in existence now is using lithium batteries and guess what they dont do? LoL! And no it is not because of the BMS placed in the pack; the battery chemistry determine's its stability. Lithium batteries used in drill packs avoid cobalt so, yes you can dead short them or drain them to zero volts and have zero safety issues. With those batteries, the BMS's main goal is to extend the battery life.

Further I would wager a considerable sum of money that there have been MORE explosions, fires, injuries, etc from FLA (flooded lead acid) batteries than Li batteries. Charging FLA batteries generate hydrogen gas and LOTS of it. I've seen plenty of cars and garages completely destroyed from an idiot charging their battery bank in a pickup bed with a topper, or well sealed garage and the moment they turn on the light, the truck/garage goes straight Hindenburg. lol

And that was with perfectly normal/healthy batteries. Much less one that is half empty attempting to be charged.

[Steve390Gold]

Originally Posted by Hilltop Ken

I purchased a 2208 EZGO RXV without batteries. I have been told that it had been converted to lithium by the previous owner. How do I convert back to regular lead acid batteries?

Holy cow you got a cart from the FUTURE!! What was it like in the year 2208?

Really no changes need to be made other than perhaps the terminal connections. The cart's controller only cares about the voltage and current that it might need, not the chemistry that generates said power.

Further, as has been quite heavily discussed, most lithium battery chemistries are very safe, it is just the lithium cells containing cobalt that are the disastrous ones when heated or excessively shorted. The only car company using those is Tesla.

Personally I HATE lead acid batteries. They have next to no power, have a very short life span due to sulfonation, and weigh a metric ton...lol In any event have fun and good luck with your project.

[sunking]

Perhaps I am missing something here, but there is nothing to do to convert back to Pb. The motor and controller do not know what the battery type is, nor does it care. As long as voltage is close is good enough.

[nickdalzell1]

So there is no monitoring circuitry/special wiring/special hold down/tray configuration?

I'm seriously not the only one scared of Li-Ion. Personally, if it were possible I'd still have a smartphone with NiMH batteries (removable as well) but today tech is controlled by the fashion industry. Id personally prefer a more rugged brick of a phone than one that's blade thin that is able to be broken by looking at it wrong. But, that's me.

Never heard of NiMHs exploding in folks' pockets.

[jkredman]

I’ve seen multiple Lion batteries swell in my iPhones when I push them beyond their useful life. The iPhone simply starts shutting down because of an over temperature issue. I was in Orlando International Airport when a camera Lion battery burst which caused a mass panic where even TSA abandoned their posts and ran like chickens with their head chopped off. Yes, damaged Lion batteries can burn, but I’ve yet to see one that burned fast enough or hot enough to injure a person assuming the person kept their head and didn’t panic. My experiences are that it is panic that hurts people; not the failure of a Lithium Ion battery.

[nickdalzell1]

I've read stories of puffed Li-Ions that gassed and from what i read, that gas isn't good to breathe in either.

I got some old iPhone 4 lying around in storage (found in junk car without SIM, activated for a short time with a Tracfone SIM and it seemed to work fine)

But iPhones must have seen the issue coming as my old 3GS that was my first Smartphone (my old favorite will remain my Nokia 5185i, kept going with spare NiMH battery packs that were going for pennies at Goodwill, and using Page Plus Cellular to avoid the e911 requirement, ran it until late 2008 ) was showing me 'Temperature--iPhone needs to cool down before you can use it' quite often.

Samsung shortcut many of the in-built protection and it eventually bit them hard. Dell had a history of laptops that exploded in a fiery mess making them also incorporate protection efuses into battery packs that cut power after a finite number of charging cycles (look up Dell 1-3-5 error and you'll find a long thread about the details)

[Rickochet]

I did the Lith conversion in 2017 using a turn key pack from EVBatteryCenter. One reason I like the pack is that I have to leave it for long periods with no charger plug in available. Last winter I left the cart at the lake at a recommended storage voltage of 37.5 volts in October. I didn't go back to the cart until April and voltage was still at 37.5 v.. Now I don't have to load up the cart, take it home hogging up garage space to keep it charged. Performance and distance is increased with the reduction in weight.

If you have a properly constructed pack with a BMS and properly charge it with the right charger chances of any issues are minimal. If they weren't safe there would'nt be so many in automobiles that are parked inside garages in homes.

[nickdalzell1]

They're only 'safe' because of the BMS and charging systems designed for them. If they were safe at all, none of that would be needed. NiMHs, and FLA never needed that mess.

Even hoverboards only got 'safe' because they redesigned the charger algorithms, OS, and designed a kind of militarized shield for the battery pack. Li-Ion is a bomb waiting to go off--volatile and dramatic when it goes in flames. Even RC guys can attest to that.