lifted club cars - lifted ezgo
Home FAQDonate Who's Online
Go Back   Buggies Gone Wild Golf Cart Forum > Golf Cart Repair and Troubleshooting > Electric Club Car > Lithium Club Car


Post New Thread  Reply
 
Thread Tools Display Modes
Old 12-19-2021, 03:55 PM   #11
Pat911
Gone Wild
Club Car
 
Join Date: Dec 2020
Location: Melbourne, Australia
Posts: 1,919
Default Re: Project Precedent

Nice project. Two limitations of the Daly BMS from my own personal experience, balance current is ridiculously small at 30mA and it does not coulomb count correctly. If it turns out to be a problem, the first limitation can be solved with an external active balancer and the second one with a quality shunt SOC meter.

Keep up the good work.
Pat911 is offline   Reply With Quote
Alt Today
BGW

Golf car forum Sponsored Links

__________________
This advertising will not be shown in this way to registered members.
Register your free account today and become a member on Buggies Gone Wild Golf Cart Forum
   
Old 12-19-2021, 07:45 PM   #12
UncleJerm76
Gone Wild
 
UncleJerm76's Avatar
Club Car
 
Join Date: Jul 2012
Location: Central FL
Posts: 1,195
Default Project Precedent

Quote:
Originally Posted by Pat911 View Post
Nice project. Two limitations of the Daly BMS from my own personal experience, balance current is ridiculously small at 30mA and it does not coulomb count correctly. If it turns out to be a problem, the first limitation can be solved with an external active balancer and the second one with a quality shunt SOC meter.

Keep up the good work.


Thanks for the comment Pat, what chemistry are you using? I’ve been top balancing my pack on my benchtop power supply going on two weeks now and still not finished. Anyway Im told that first-time proper top balancing will be enough for the 30mA balancing to be effective. From everything I’ve read about matched lifepo4 cells, if top balanced they will remain very close to each other unless high rate of discharge occurs regularly. I will be keeping a close eye on it through the Bluetooth app to see if that’s true. But I don’t ever expect to exceed 1C on this stock cart, I tried before starting my top balancing and couldn’t get past .5C - now later down the road with the AC conversion it might be a different story. My bigger concern right now is fast charging (not really, just 15-20a but) might not allow enough time for the balancing to finish before the charger kicks off since balancing only occurs at the upper end of the SOC. It will be an experimental process - I might need to slow down my charger to give more time for balancing I will have to wait and see if 30mA is enough to keep up.

Interesting news about the 2nd issue, I have not heard anyone report the issue with coulomb yet, is this documented anywhere or strictly personal experience? I did get a SOC meter and shunt - not sure of it’s quality yet but I will verify it’s voltage and current against my Klein handheld after the pack is back in the cart.


Sent from my iPhone using Tapatalk
UncleJerm76 is offline   Reply With Quote
Old 12-19-2021, 08:09 PM   #13
UncleJerm76
Gone Wild
 
UncleJerm76's Avatar
Club Car
 
Join Date: Jul 2012
Location: Central FL
Posts: 1,195
Default Project Precedent

I guess the wiring is “a little” more organized then from the factory but I was hoping for more. For a temporary solution it will have to do. When hooking everything back up I realized why Club Car angled the controller! This was to allow stress relief on the lugs at the controller! I didn’t like all the extra stress those cables making a hard right put on those lugs now so I put some right angle lugs on it and that fixed it great. Overall I’m very pleased I was able to fit everything under the center console and it will still look more or less like a stock cart under the seat. I might tweak a few things here and there (like a 12v reducer on the other side) but I’m calling the console “done” at least the hard part anyway.

Still need to sort out a few items before it’s ready to ride. Like how I’m going to secure these lithium packs to the cart, protect the top terminals from accidental shorts and finding an eye-pleasing solution for the BMS balance wires.





Sent from my iPhone using Tapatalk
UncleJerm76 is offline   Reply With Quote
Old 12-19-2021, 08:58 PM   #14
Pat911
Gone Wild
Club Car
 
Join Date: Dec 2020
Location: Melbourne, Australia
Posts: 1,919
Default Re: Project Precedent

Hi UncleJerm,

LiFePO4 is what I’ve had it connected to. A 4s 12v 200Ah pack or be specific. 30mA certainly doesn’t keep up with my 40A charger and I top balanced for two weeks before building the pack.

Onboard SOC is my personal experience. During the testing phase I had a 12v fridge connected, it ran for 9 days. When the battery hit the low voltage cutoff, the DALY app still showed 85% battery capacity. My belief, without investigating further is that it fails to count current less than 1 amp, as the app does not display currents under 1 amp. Any current under 1 amp is displayed as zero.
Pat911 is offline   Reply With Quote
Old 12-19-2021, 09:05 PM   #15
UncleJerm76
Gone Wild
 
UncleJerm76's Avatar
Club Car
 
Join Date: Jul 2012
Location: Central FL
Posts: 1,195
Default Re: Project Precedent

Quote:
Originally Posted by Pat911 View Post
Hi UncleJerm,

LiFePO4 is what I’ve had it connected to. A 4s 12v 200Ah pack or be specific. 30mA certainly doesn’t keep up with my 40A charger and I top balanced for two weeks before building the pack.

Onboard SOC is my personal experience. During the testing phase I had a 12v fridge connected, it ran for 9 days. When the battery hit the low voltage cutoff, the DALY app still showed 85% battery capacity. My belief, without investigating further is that it fails to count current less than 1 amp, as the app does not display currents under 1 amp. Any current under 1 amp is displayed as zero.
Wow that very unfortunate. If that's the case with all Daly's then that is going to be a problem. Question; How did it recognize and initiate low voltage cut off while still reading 80% state of charge?
UncleJerm76 is offline   Reply With Quote
Old 12-19-2021, 09:22 PM   #16
Volt_Ampere
Gone Wild
Yamaha
 
Join Date: May 2012
Location: Rio Verde, Az
Posts: 7,119
Default Re: Project Precedent

My home grown BMS does balancing at 1 amp. That seems to me to be a minimum for these larger packs (mine are Leaf) Mine do stay nicely in balance once I got them initially balance. My balance mode is not automatic. I do it when needed. (maybe once every couple months)
Volt_Ampere is offline   Reply With Quote
Old 12-19-2021, 10:26 PM   #17
Pat911
Gone Wild
Club Car
 
Join Date: Dec 2020
Location: Melbourne, Australia
Posts: 1,919
Default Re: Project Precedent

Quote:
Originally Posted by UncleJerm76 View Post
Wow that very unfortunate. If that's the case with all Daly's then that is going to be a problem. Question; How did it recognize and initiate low voltage cut off while still reading 80% state of charge?
It recognised the minimum cell voltage I set. The BMS functioned as it should, protecting the pack, it just didn’t count down the state of charge correctly.

@Volt_Ampare, 1A is a good choice for balance current.
Pat911 is offline   Reply With Quote
Old 12-20-2021, 08:31 AM   #18
Volt_Ampere
Gone Wild
Yamaha
 
Join Date: May 2012
Location: Rio Verde, Az
Posts: 7,119
Default Re: Project Precedent

The trick using higher balance currents is that you have to ignore cell voltage during the balance discharge on time. My balancer turns on the current on the high cells for 8 seconds, turns it off for two, measures all cells, repeat until balanced. I only balance after charging so cells are all just over 4 volts (Top Balance) My balance routine runs until all cells are within 10mV of each other. Usually takes a few minutes once a month or so.
Volt_Ampere is offline   Reply With Quote
Old 12-20-2021, 09:02 AM   #19
WalterM6
Gone Wild
 
WalterM6's Avatar
Club Car
 
Join Date: Apr 2017
Location: SE TN
Posts: 2,217
Default Re: Project Precedent

Another problem with the Daly is that there isn't any static balance mode. I've been trying to get my batteries balanced since July. After a full charge the voltage difference was 130mv. After my Daly died, I installed a JBD BMS. After two charge cycles and switching to static balance mode the difference is already down to 75mv.
WalterM6 is offline   Reply With Quote
Old 12-20-2021, 09:41 AM   #20
UncleJerm76
Gone Wild
 
UncleJerm76's Avatar
Club Car
 
Join Date: Jul 2012
Location: Central FL
Posts: 1,195
Default Re: Project Precedent

I wonder if leaving my bench-top power supply connected to the 48v pack at a CV with a very low Amperage would allow the Daly enough time to balance …I see lots of experiments in my future.


Sent from my iPhone using Tapatalk
UncleJerm76 is offline   Reply With Quote
Reply

Tags
club car, daly, lifepo4, lithium, precedent
Go Back   Buggies Gone Wild Golf Cart Forum > Golf Cart Repair and Troubleshooting > Electric Club Car > Lithium Club Car


Thread Tools
Display Modes


Similar Threads
Thread Forum
My 2005 Precedent - First project Members Rides
11 Precedent Project Members Rides
Latest Project, 72V Precedent Electric Club Car
Precedent hunting project Lifted Golf Carts
Our New CC Precedent Project Lifted Golf Carts


All times are GMT -5. The time now is 04:55 AM.


Club Car Electric | EZGO Electric | Lifted Golf Carts | Gas EZGO | Used Golf Carts and Parts

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
This Website and forum is the property of Buggiesgonewild.com. No material may be taken or duplicated in part or full without prior written consent of the owners of buggiesgonewild.com. © 2006-2017 Buggiesgonewild.com. All rights reserved.