This is a 2 part post and will likely be long winded:
Looking for insights on how, if even necessary, to correctly bypass the factory installed Delta Quiq charger. I own a golf cart repair business and a customer purchased a 2019 GEM e6 with bad batteries and an ECO 51v 160AH lifepo4 battery/charger bundle. I installed everything including the new charger in the rear battery compartment. I left the OEM Delta charger in place and did not make any changes to any of its DC connections. I cut and spliced the wires coming from the back of the OEM charge port and ran AC power to the ECO charger.
This was about 6 weeks ago. The cart runs great as far as I know (I haven’t heard any complaints). I’m inexperienced with GEM vehicles and it never occurred to me that there might be other components impacted by not utilizing the DeltaQ charger.
Then last week another GEM I replaced batteries in 8 months ago started having problems. I replaced the LEOCH 6v gel batteries with Trojan T105AES AGM units and did not make any changes otherwise, including the algorithm in the factory charger. That cart has been running fine for 8 months and 1200 miles (both of these carts live at homes that are vacation rentals and the carts are driven a TON). I was called out for a complaint that this one wouldn’t turn on. Found the 12v battery in the dash was dead. Replaced it and everything worked fine. I did not think to check that voltage increased on the 12v battery when the key was on. The very next day the cart was inoperable again. I returned and the 12v battery was down to 8v already so I knew it was not charging like it should. Because of the urgency of having it fixed for guest use and my lack of advanced knowledge with GEMs, I referred my customer to the local GEM dealer. They found the DC converter faulty and replaced it for a whopping $1200. They then told my customer he needs all new batteries because the ones installed were incorrect for a GEM and had not been charged properly. Since I’m responsible for the batteries I advised my customer to request the dealer change the algorithm to the profile for the batteries in it and have it returned to his property so I could verify any issues with the batteries.
When I arrived the cart was connected to the charger had 51.8V but the DeltaQ had a fault (mistakenly didn’t observe the number of flashes yet) and the SOC reads 0 charge. Everything else works in the cluster and the cart was driven for 7 miles with a DVM connected both to the total pack and then each battery individually for multiple full throttle jaunts up to 25mph. After 7 miles, total voltage never dips below upper 45v range and none of the batteries individually drop below 5.7 at peak acceleration. Once cruising at 25mph pack voltage is upper 49v. Parked the cart after 7 miles and left it for an hour and ran another call. When I returned, resting pack voltage was still 51v. Those voltages seem to be normal in my experience, albeit I primarily deal in the more standard golf carts/LSVs.
The SOC was working fine for 8 months before it went to the dealer for the DC converter. I’m offering to remove the batteries I installed and refund my customer and let the dealer handle it, but they’re quoting him $5400 for batteries and he is (rightfully so) apprehensive. He and I both feel something fishy is going on since everything was fine for so long. He is willing to give me the opportunity to fix it or swap in the ECO lithium bundle at a discount. Is there something simple that might be causing the SOC not to register? The vehicle runs fine otherwise.
Thanks in advance for any help. I tried searching for both of these issues but didn’t really see any exact replicas of my issues and the closest ones I found did not really have clear resolution. I have acquired the SpeedBX for this customer and will be going out to install in a few days, so it would be a good time to do any bypasses that may be necessary.
I would walk away from Any of the Chinese batteries, get one of the @LithiumGods Batteries, he will get you all you need to use with the factory charger.
The 2016+ Gems need to use the factory charger for everything to work properly. It got by for a while the way it was setup but eventually there will be problems. First, the Gem only charges the 12v when the Delta-q is plugged in or the key is on. Since you weren’t using the factory charger , it only charged the 12v when running. This will be hard on it and cause it to fail. It needs to be maintained properly by the system. The part I find interesting is that you are saying the Eco battery with a direct hooked up charger still had the Soc gauge functioning. That gauge is suppose to only work when charged thru the DQ. Usually if you charge directly it will trigger a limp mode in the system. Would like to hear more about this setup. FYI the dc charger’s week link is the plug, It fails frequently. Most of the time if you remove and clean, it will work fine.
I have a few options that are double the range of the Chinese lithium batteries, made by Ford, works with factory components and cost just a little more. Also we can support you on all your Gem issues so that your clients wont be paying for expensive repairs.
You mentioned using Gabe’s Speedbx, I offer a discount on a batteries for anyone using a speedBx
I commend you for standing behind your work and offering a refund. Lets get you something your client will LOVE and you can make some money for your effort.
Thank you both for the insight. At this point, I do not think I’ll be offering a refund on the GEM with the ECO lithium installed since that customer specifically wanted it. If anything I may just go run AC power back through it’s still installed DeltaQ and let the dealer change the algorithm. My local GEM dealer installs Bolt lithiums in everything they convert, including GEM cars, I’m just not sure what they’re doing about the charging.
The other cart’s (the one with the Trojan AGM batteries) issue seems to have resolved itself. Maybe it just needed a few extra charge cycles after the dealer changed the algorithm. I went to pick it up yesterday morning to return it to the dealer and low and behold, it showed a full charge on the cluster
I am down a rabbit hole with my 2015 Gem EM1400 LSV. Having not a clue what was doing, I ordered a Hysincere 51.2V 105 OA 4000 cycle 10.24 KW lithium Iron battery to replace my original lead acid. Didn’t take long to discover that the Delta-Q is integrated into the car and can’t simply be swapped with a Lithium charger. I have seen in the posts that you provide algorithm updates the the Delta Q? Thanks for advising if this is a service you can help me with. I can ship it to you with return label.
If advertised as 10.24kw battery, it was to confuse the buyer. It would normally be rated in a more meaningful kwh. In your case 5.38kwh.
Em-1400 s are 48v and battery should be fine, giving over 20 mile range. Just not the 40 miles expected from a 10kwh battery.
Have you tried leaving everything as-is, and just dropping in the new battery? I suspect that it will charge fine, albeit slow. I haven’t needed to reprogram my Emmy chargers when swapping to lithium.
It may trip bms when hot off the charger, with regen, depeding on charger finish voltage.
58.4v is bms over voltage for your 16s lfp battery.
She has 8 x 6v lead acid batteries on board now. They froze this winter (welcome to Minnesota) and are shot. If staying with lead acid is the recommendation, I can go that direction. The car has less than 500 miles on it so I would also be open to investing in a different solution if recommended? It’s worth investing in.
He may be waiting for your opinion, as he is talking about not using the battery he has and going back to la.
I thought I made it clear that he should see 20 miles range from his 5kwh battery. Of course, we don’t know the specs. Emmy has a s4 450a controller.
What do you think?
I charged up the Lithium outside the car and dropped it in to take it for a spin to see how it would perform. The battery burned up 20% in about 2 miles. It is in no way big enough for the GEM. It will make a great trolling motor battery for someone down the line!!! Back to LA I go!
That poses the next question, should I have my charger converted and give the LI pac a try? LA batteries for that cart will be bumping up against $$1500 for quality batteries. It might be fun to see how the Lithium works if I give it a chance. One round through the gravel pit probably didn’t do it justice?
See how far it goes before worying about the charger.
Unless your charger can’t full charge. It should charge to 57v or so.
A lithium charger for that battery is 58.4v, iirc.