Allied battery

[1swampthing]

Almost a year ago I purchased a 100ah lithium battery from allied. It is the 4 12v batteries in series not the new 48v parrallel. From the beginning they refuse to stay in balance. One battery will get to about 14.5 volts then quickly climb to 18 plus volts which then trips the charger off while the other 3 batteries may only read about12.9 to 13.1v. After several dealings with allied they sent me a 12v charger and told me to remove batteries and parrallel them and charge with 12v charger to get back in balance. At end of this charge all are 14 plus, don't remember exact number. When put back in cart the next 48v charge they will be about 13.35 and performance will be good for 6 weeks to maybe two months. But will be slowly getting out of balance. I know I have issues but starting several months ago my cart started randomly shutting off. Goes again immediately by letting off on pedal and pressing it again. Posted question about it on club car electric forum and was advised to ask on lithium form if my battery issue could cause it. Thing is that shut down occurs regardless of state of charge of battery or if is freshly balanced

[Pat911]

Hi,

A couple of things, Have you bypassed the OBC? And, If one of your 12v lithium batteries got to over 18v, it may very well have one or more bad cells in it, although it’s BMS should have prevented such a high voltage.

Your experience is the exact reason that series connected lithium batteries should never be used. Not in a cart, not in anything. A single battery of the appropriate voltage must always be used, but I think you already know that.

Cheers
Pat.

[1swampthing]

Yes obc is bypassed. The high voltage that one battery gets is actually like a surface charge since merely backing cart out of garage will drop voltage to around 14. Yes I have learned a VERY expensive lesson. I use my cart every day and hated having to frequently clean the tops. Seem I got acid on top due to frequently being on rough terrain and lithium looked like a possible solution to less maintenance but now I have to remove and rebalance frequently so more maintenance than before

[kgsc]

Well they are a sponsor now so maybe they can suggest what to do next..

[Fairtax4me]

I read your other thread, and I'm not sure it's battery related, but since you are having battery issues the guys here who know lithium setups should be able to help you determine if something is going on with the pack that would cause your problem.

Some time in the early and mid 2000s Club Car had a problem with solenoid dropout caused by the regen system on the cart. There was a diode built into the wire harness somewhere (can't remember exactly) that was there to prevent back-feeding of voltage during regen. The main symptoms was on the solenoid activation circuit, where it would cause the solenoid to drop-out (to open) and the cart could go into roll away braking. The reverse buzzer might also beep while that was happening. Releasing the pedal and pressing again would reset the solenoid and the cart could keep going. Sometimes, but not always the controller would set a Main Dropout error, but you can only check those faults with an IQDM scanner.
This was a problem on the IQ carts, I'm no sure if excel carts were also affected.

But there are other reasons the solenoid can drop out, loose connections, frayed or damaged wiring, or an internal issue with the solenoid.
A problem with the FnR switch can cause similar symptoms if the controller loses the FnR signal while driving. Same for the Key switch input, or the OBC input. With lithium batteries I'm guessing you've bypassed and/or removed the OBC, but make sure the wire connections for the bypass are still good.

[WC53]

Doesn’t Allied offer balancers to use with the old 12v? There is an old thread somewhere and the installer retrofitted all his previous installs with balancers and rectified the one issue . Maybe they were 3rd party?

[1swampthing]

They do offer balancers and I have had one on it since day one. The balancer stays warm 24/7 which over time I am sure is something of a constant draw on the batteries. The last time I checked with digital thermometer temp was over 100 on the balancer. Maybe it helps but certainly doesn't keep it in balance. The above post talking about the diode causing the solinoid to drop out sounds very plausible to be my problem. I don't think I have a loose wire issue since symptoms are always exactly the same. If I have pedal half way depressed when it dies nothing happens pressing pedal further down but when you let off the pedal as soon as you start to depress you hear solinoid pick back up and you are running again. I replaced mcor and solinoid and symptoms unchanged

[Pat911]

Fairtax4me gave some very good suggestions.

Back to the batteries, a 12v lithium battery (LiFePO4) should NEVER have greater than 14.8v (3.7v per cell). That battery is shot. Even if that battery is the first to be fully charged, the BMS should disconnect. At that point you should see the full charger voltage on that battery, but as the BMS is off, no current will flow and the cells will not see that voltage. To see 18v indicates that the BMS hasn’t shut off and that voltage is applied to the cells. Not good.

Cheers
Pat.

[1swampthing]

After charging battery last night checked voltages. 3 batteries were 13.33 each. The 4th was 18.49 until I unplugged charger and immediately dropped to 14.73 when tells me 18.49 is not a true reading. Once I watched volt meter while charging and at 14 point something it when up to 18.something in a matter of seconds and then charger shut down. Actually this morning's reading are not bad since I just balanced the battery about 3 weeks ago. Series batteries suck due to frequent rebalance but I seriously doubt it is cause of cart shutting down. This morning cart shut down about 100yds after I pulled out of garage and about 3 more time through the course of the morning. State of charge has no effect on my problem

[WC53]

The 13.3 would be about 50% and the other at 100%? Would any regen then push the top cell into overvolt and shut it down thus killing the cart and that cell