Lithium starting battery question

[Bauer]

Hello

I am taking over ownership of a 1997 EZGO TXT gas cart and am looking at adding a stereo to it. It also happens to be time for a new battery and I have access to lithiums at a discount. Is it possible to install a lithium starting battery in one of these carts with the current charging system that is on it? If not, what upgrades may be needed to do so?

I like the idea of a longer discharge time considering the stereo and other things that may be drawing juice.

Thanks in advance!

[CP241]

I think I’d just buy an optima and be done.

Lithium batteries generally need a pretty tightly regulated charging system. A golf cart is not that. I don’t know what particular batteries you have access to, but if BMS cuts off charging at anything above 14.5v it probably would be even be charging half the time you are driving the cart anyway. Golf carts often charge anywhere from 14-16 volts depending on various factors.

[Pat911]

I initially refrained from posting as I always seem to come across negative when things are done that are a little out of the left field. I like to do things by the book, and charging lithium from an alternator is certainly not by the book.

As CP241 said, I would just go with an AGM or LA starter battery and if you want extra power for your 12v accessories, then get a DC-DC Lithium charger and drop in a second lithium battery just for the accessories. That will ensure the Lithium battery gets charged correctly.

Another problem that may arise if you do go with a single lithium solution is that if/WHEN the BMS disconnects on high voltage, the full alternator output will be sent to your accessories. I know this is bad in a car, as the voltage will rise dramatically, but I don't know how cart charging systems work.

Cheers
Pat.

[CP241]

Originally Posted by Pat911

I initially refrained from posting as I always seem to come across negative when things are done that are a little out of the left field. I like to do things by the book, and charging lithium from an alternator is certainly not by the book.

As CP241 said, I would just go with an AGM or LA starter battery and if you want extra power for your 12v accessories, then get a DC-DC Lithium charger and drop in a second lithium battery just for the accessories. That will ensure the Lithium battery gets charged correctly.

Another problem that may arise if you do go with a single lithium solution is that if/WHEN the BMS disconnects on high voltage, the full alternator output will be sent to your accessories. I know this is bad in a car, as the voltage will rise dramatically, but I don't know how cart charging systems work.

Cheers
Pat.

Good point about when the BMS disconnects and all the accessories in the cart are now being run off the generator. Didn’t think about that side of it. The battery doesn’t just “store energy” to make stuff work. It also acts as a big buffer to absorb and smooth out spikes and noise inherent in the operation of an alternator/generator. Without the battery to stabilize everything so to speak the voltage willl be much “dirtier” and noisier. Certainly not good for your stereo or anything else. But definitely not good for your stock ignition components, which you can’t replace anymore. They’re long discontinued and if they go bad the only options are aftermarket China parts…. Which by far and large suck.

[Pat911]

The exact point I was trying to make

[Bauer]

Thanks for the info, I have access to Pro Guides and Dakota Lithium's, and understand the BMS issue in cheaper batteries. I am a 12v guy, but lithium's and how they charge still are Greek to me as I have not taken the time to understand them. I find it rather hilarious that these companies advertise starting batteries, but don't take the time to explain how correct charging systems are necessary. Mercury Marine took the initiative and got the information out right away that they strongly state you should not use a lithium as a starting battery and they will likely not warranty anything if you do. Not much there from the rest of the world including the auto industry.

[Leon willis]

I wonder which is safer lead acid or lithium?

[CP241]

Originally Posted by Pat911

The exact point I was trying to make

Absolutely. And I’ve never taken anything you’ve said as negative a little surprised to see you over in the gas world but you’re always welcome!

Bauer, yes the lithiums require a much stricter charging methodology. As pat said if you want a lithium for the accessories then cool. Victron makes a nice 12v-12v dc-dc charger designed for charging an auxiliary lithium battery. The cheap 9amp one is about 70 bucks and takes anywhere from 10-17 volts and gives you an adjustable output to charge the lithium battery that you can set at whatever voltage your particular battery requires and it will stabilize that output voltage so no matter what is coming in, the output remains constant. But between the lithium battery, the converter, and the headache. I think I’d just buy a yellow top and be done :)

[Pat911]

Thanks for the welcome CP, I always poke my nose in when I read the word lithium….

Maybe it’s just me thinking I’m being negative as I seem to be repeating myself constantly. Do I sound like a broken record?

Originally Posted by Leon willis

I wonder which is safer lead acid or lithium?

Lithium, LiFePO4 especially, is very safe when used correctly, safer than lead acid as there’s no gassing while charging. The key is using the battery correctly, especially charging with the appropriate charger and protecting it from being discharged below 2.5v per cell, but that’s the BMS’s job.

Cheers
Pat.

[CP241]

Originally Posted by Pat911

Thanks for the welcome CP, I always poke my nose in when I read the word lithium….

Maybe it’s just me thinking I’m being negative as I seem to be repeating myself constantly. Do I sound like a broken record?
Cheers
Pat.

I think we all feel that way from time to time