48v Lithium 48ah pack

[matthejl]

Would a lithium pack thats rated at 48ah...be comparable to running 12vx4 lead acid batteries? Considering you run those to 50% and lithium you can run all the way down?

[DaveTM]

You can't "run lithium" all the way down. Lithium has a low voltage point that when it gets lower than that, the battery is damaged. It only takes one time.

[Bama Brad]

Welcome to the forum....I don't think a 48ah will be near sufficient to run a golf cart for very long.

[Tom47]

That 48Ah pack will give you a safe usable Ah of 34.5. This is based on 90% settling voltage of 53.2 and a safe minimum SOC of 20% and 51.2 volts. You can go lower occasionally to get the cart to the barn. This 90% will be calibrated as 100% on your SOC meter.

For flat paved road use, you can estimate 1.5 Ah per mile. This has been true in my case over 10 documented rides from 8 miles to 27 miles per trip. My 72 Ah battery gives me a range of 39 miles safely. I charge after each trip of a mile or more.

Your cart drive setup, speeds, conditions, etc. may affect this estimate. You could expect 20 miles per charge cycle based on this. (48Ah, -10% settling charge, -20% minimum SOC, divided by 1.5 equals 23 miles.) My formula may not work for all users.

If golfing, I'm not sure what this mileage would correlate to.

[matthejl]

Originally Posted by Tom47

That 48Ah pack will give you a safe usable Ah of 34.5. This is based on 90% settling voltage of 53.2 and a safe minimum SOC of 20% and 51.2 volts. You can go lower occasionally to get the cart to the barn. This 90% will be calibrated as 100% on your SOC meter.

For flat paved road use, you can estimate 1.5 Ah per mile. This has been true in my case over 10 documented rides from 8 miles to 27 miles per trip. My 72 Ah battery gives me a range of 39 miles safely. I charge after each trip of a mile or more.

Your cart drive setup, speeds, conditions, etc. may affect this estimate. You could expect 20 miles per charge cycle based on this. (48Ah, -10% settling charge, -20% minimum SOC, divided by 1.5 equals 23 miles.) My formula may not work for all users.

If golfing, I'm not sure what this mileage would correlate to.

Super appreciate a useful answer. My current lead acid pack will get me 15 miles safely, 15-20 would be pushing it, but capable. This is decently flat, with some hills. The question was would this "smaller" lithium battery be comparable to 12vx4 pack. According to this answer...it would be. I know that the enthusiasts that have tons of money to spend are going to shun this question and say its crazy, etc...I dont make big long runs often, $600 is alot different than $1700-$2000...which led to me even asking this question.

So lets so I did go this route, which I dont know if I would...I could still use a standard voltage digital readout...and make sure it stays in the safe reading of low voltage?

once again...thanks for the useful information.

[matthejl]

Originally Posted by Tom47

That 48Ah pack will give you a safe usable Ah of 34.5. This is based on 90% settling voltage of 53.2 and a safe minimum SOC of 20% and 51.2 volts. You can go lower occasionally to get the cart to the barn. This 90% will be calibrated as 100% on your SOC meter.

For flat paved road use, you can estimate 1.5 Ah per mile. This has been true in my case over 10 documented rides from 8 miles to 27 miles per trip. My 72 Ah battery gives me a range of 39 miles safely. I charge after each trip of a mile or more.

Your cart drive setup, speeds, conditions, etc. may affect this estimate. You could expect 20 miles per charge cycle based on this. (48Ah, -10% settling charge, -20% minimum SOC, divided by 1.5 equals 23 miles.) My formula may not work for all users.

If golfing, I'm not sure what this mileage would correlate to.

What's a good calibratable...if that's even a word...but SOC for a lithium pack? A generic one.

[Tom47]

Originally Posted by matthejl

What's a good calibratable...if that's even a word...but SOC for a lithium pack? A generic one.

I understand this is a good one. It comes highly recommended by the pros here.

https://www.amazon.com/Renogy-500A-B...364315&sr=8-13d

This is similar to what I have:

https://www.amazon.com/AiLi-Voltmete...364489&sr=8-18

[matthejl]

Originally Posted by Tom47

I understand this is a good one. It comes highly recommended by the pros here.

https://www.amazon.com/Renogy-500A-B...364315&sr=8-13d

This is similar to what I have:

https://www.amazon.com/AiLi-Voltmete...364489&sr=8-18

And these are fully programable for each owns specific setup?

[Pat911]

Don’t know about the AiLi unit but the Renogy is fully programmable.

A 48Ah pack would be comparable but make sure the pack is a single 48v pack, not 4 12v packs and that the cells and the BMS can handle the current requirements of your cart. You don’t want your BMS shutting off when accelerating. Most cheaper cells can only handle 1C or 2C discharge, that’s only 48A or 96A, which won’t be enough. Do you have a link to the specific pack you’re looking at purchasing?

Cheers
Pat.

[DaveTM]

My ZEVA BMS has a screen that shows amp\hrs along with the pack voltage.

I'm not an engineer and have some understanding of amp\hrs on a read-out device, but frankly I never pay attention to it.

What I look at is the pack voltage at rest. I know I'm fully charged when my volts read 57V. And I know that when my volts read 50.0 at a rest......I have very little run time\distance left.....like a few hundred yards to be safe.

Usually I recharge when the pack hits 51V at a rest.

FWIW