72v vs 48v lithium setups?
 

My current batteries are new and will use them till they go. My plan has been to upgrade to 72v lithium when the time comes. Do I need 72v? I know my speed will increase, would like roughly 30+- mile range. Any reason I should consider 48v lithium?

I’m currently seeing 32-36mph on my setup. Would 48v get me more then 1-2 mph more?

Believe 72v will give me 45-50mph speeds which is flying. I would prolly tune it down.

Re: 72v vs 48v lithium setups?
 

You can easily get more than your requested 30+ miles of range at 48v or 72v.

As for max speed, I limit my 48v carts speed currently. With my lift and setup it feels fine up to about 24/25mph even though it can do 34mph before it reaches the motor max rpm.

That's what set my cart's max speed, max safe motor rpm (6,000) and how twitchy it gets at speed. What is your motor max RPM? Do you have high speed gears in the diff? Most golf cart motors have a 6k safe limit, beyond that you are on borrowed time. Is your motor an aftermarket one with high speed banding to allow for greater speeds?

Using the speed calculator (https://www.buggiesgonewild.com/speed-calculator.php) you can plug in your motor max RPM, tire diameter and axle ratio and see what your theoretical top speed is.

As for 48v vs 72v you can do either. Both have plenty of accessories available. There are far more 48v options out there for accessories/batteries/controllers/motors than 72v but both absolutely exist. If you are at your max speed currently then either lithium pack will do the same for you. 150ah 48v pack is the same number of cells in a different configuration than the 100ah 72v pack. So if both options were available from the same manufacturer I'd expect the prices to be similar. In reality the 72V will likely be a little more expensive while also being slightly more efficient. A 100ah 72v pack will have far more range than a 100ah 48v pack but for apples to apples (and price to price) it's 150ah48v to 100ah72v. Wild guess (assuming no extra drag issues) is you will probably around 60 miles of range on a 150ah48v or 100ah72v pack. Probably around 40 miles on 100ah48v. Driving habits and driven speed affect this greatly. My range is incredible if I stick to 19mph and is pretty good if I roll at 27mph.

You asked if there is any reason to consider 48v lithium but the other question, "is there any reason to consider 72v lithium", is just as valid. But in order to help either way we need to know what you want from your cart really. Do you actually want 50mph? Do you want 30 miles of range while traveling 50mph or when going that far do you normally travel slower? Are you willing to replace the motor or put in high speed gears in the diff? Is your cart very stable at it's max speed today?

Re: 72v vs 48v lithium setups?
 

Want to go real fast in a golf cart?

Re: 72v vs 48v lithium setups?
 

ouch! Wow, that's at only 50kph too! That's basically 31mph when it folds up like a taco!

Re: 72v vs 48v lithium setups?
 

Makes sense when these are designed to be driven around at 15mph or less.

Re: 72v vs 48v lithium setups?
 

I live in a boating community. Family/friends houses are all 1-4 miles away along with restaurants/entertainment. I’ll drive 5-20miles any given day. I feel like I’ve made all necessary improvements/safety measures for my cart. Just debating on batteries when the time comes. I have no problem running 25+Mph in my cart, have to run faster sometimes to be safe with traffic. I know my 5kw AC setup will come to life with 72v. Almost feel like I will be leaving performance on the table if I don’t go 72v. My current speeds are plenty fast 99% of the time.

Re: 72v vs 48v lithium setups?
 

On paper there should be no difference between a 48v or 72v system when it comes to AC drive. There is no relationship between the supply voltage and what the controller passes to the motor.

Very simply, In an AC drive system, DC power is supplied to the controller and the inverter in the controller converts it to an AC signal and varies the frequency and amplitude of the AC signal given to the motor to vary the speed, torque etc.

The only difference between a 48v and 72v system is that less current is drawn from the 72v battery for the same performance. You need to think in watts, not volts.

Having said all that, at least one user here has reported a performance increase when going from 48v to 72v with their Navitas. Maybe this was perceived to justify the cost of the 72v battery, maybe the test conditions weren’t the same, maybe something else changed, etc. temperature or tyre pressure, maybe there’s some trickery in the Navitas, who knows. So make of that what you will.

Cheers
Pat.