Cut bait and sell or more upgrades

[eldrima]

A few other details on my cart and usage:
I have not upgraded the F/R switch since doing the controller upgrade. At most I put about 5 miles on the cart in a day. Usually 2.5 miles or less. My town has a limited amount of 25mph roads that the carts are allowed on.

[eldrima]

Ok guys...thanks for being patient with me. I really appreciate all the help and suggestions everyone has offered so far and thank you for reading this long post. I've had a lot going over the last 2 weeks and finally took the time to get some data for you. I've gotten as much info as possible for y'all to hopefully help me figure this out.

Before doing any testing I decided to check the tire pressure with a cheap gauge that has the white plastic stick with pressure readings and it didn't move it at all. I have 23x10.5x12 off-road tires on the cart...tires are showing some wear and I never go off road with it so I'm open to changing that up a bit if you think it might help. I inflated them to about 24 PSI each.

@kernal I charged the batteries and unplugged it for about 4 hours. I have 8 Crown CR220 6 Volt batteries that look like they were made in February of 2020 (they were in the cart when I bought it back in November or so. A search suggests these are 60 lbs each so a total weight of 480 lbs for my pack. It came with a Lester Summit II charger (model 30600). Using the Lester Charger Connect BT app I was able to figure out it has battery profile 22252 and system profile 29230 (all Greek to me).

The entire pack read 50.1 volts. Each 6V battery tested at 6.2 or 6.3 individually. I hooked up the multimeter to the pack with alligator clips as you suggested and tested it on the hills. I saw an initial dip as low as 39.0V with sustained uphill readings ranging around 43.0 - 45.5. When I was done with the 5 minutes or so of hill testing the overall pack was still reading 50.1 when at rest. You can look at the video I created (link later in the post) to see the steepness of hills I'm seeing these changes of voltage on.

@bronsonj I'm not sure what gears I have in the rear diff...is there an easy way to check that? The Plum Quick motor came with instructions warning about running it at excessive speeds going down hill as it could damage the motor so I coast down hill on these steep hills.

On a flat surface I was running about 18-20 mph. Sustained uphill grades probably average around 14 mph. The steepest grade in the neighborhood drops to around 9 mph and then increases as you get past the steepest part. If you want to see some video footage of the speed when driving around, I had my daughter film from the middle row with a speedo app running on the iPad. Here is a link to the video I put together: https://www.wevideo.com/view/2269812300

I'm not opposed to building my own lithium pack but honestly know zero about that and would need some very detailed DIY video or online instructions on how to do it. Don't want something that will cause a fire as the cart is always parked in the garage with my daughter's room above. If the consensus is upgrading to a lithium pack, I'd probably lean towards purchasing one that comes with a warranty and a little more peace of mind.

If y'all need more data, I can run a log off the Alltrax controller. I'm sure going to a lithium pack and cutting 400 lbs of weight would help out. My goal though would be to have a cart that can run up to about 30 mph on flat surfaces and take the hills at 25 mph. My guess is I'll need to go the AC conversion route with the 600A Navitas to do this. If I could recoup a good bit of my recent motor and controller investment, I'd probably be willing to go that route. What do you all think?

[ThreeCW]

Originally Posted by eldrima

I charged the batteries and unplugged it for about 4 hours. ... The entire pack read 50.1 volts. Each 6V battery tested at 6.2 or 6.3 individually. ... When I was done with the 5 minutes or so of hill testing the overall pack was still reading 50.1 when at rest.

With your pack at 50.1 volts, you are at about an 81% state of charge (see attached State of Charge Chart). It appears that your batteries are not either accepting a charge or your charger is not charging them fully. To troubleshoot this, you will want to monitor your charging voltages and compare them to the attached charging voltages ... which are the Trojan values ... but other batteries should use "similar" charging voltages.

So at first look, your battery pack appears to be under charged ... which can result in some degree of under performance as well. On the other hand, you have a large and heavy cart and may be speed limited based on that ... let's see what others have to say about that.

[eldrima]

Originally Posted by ThreeCW

With your pack at 50.1 volts, you are at about an 81% state of charge (see attached State of Charge Chart). It appears that your batteries are not either accepting a charge or your charger is not charging them fully. To troubleshoot this, you will want to monitor your charging voltages and compare them to the attached charging voltages ... which are the Trojan values ... but other batteries should use "similar" charging voltages.

Thanks for weighing in on this one!

[CartsRFun]

Hey eldrima..

From Crown batteries:

https://www.crownbattery.com/hubfs/D...-Batteries.pdf

Below is a copy paste from the above link..

Renewable Energy Charging Systems
To maximize performance and life batteries should be recharged
fully after each discharge period. To verify full recharging,
regularly monitor individual battery voltage and specific gravity.
As a general rule, the total input amperes from your RE charging
source should be between 10% and 20% of the total amperehours (20 Hour Rating) of the battery system capacity. Many RE
charge controllers have adjustable equalization settings that ensure
batteries are regularly restored to full capacity. Batteries used in RE
systems should be equalized every thirty days at a minimum – with
System Voltage
Voltage Setting........................ 6 V 12 V 24 V 36 V 48 V

Daily Charge (Absorption)...........7.3 14.5 29.0 43.6 58.1

Equalize ..................................7.7 15.5 31.0 46.4 61.9

Float........................................6.8 13.5 27.0 40.5 54.0

Best wishes
Happy cartin'