2005 GEM e4 - battery options

Hi I am new to this forum and it looks like just what I need to better understand my 2005 GEM e4 options and maintenance. I currently have 6 Trojan 30XHS flooded batteries with the DeltaQ QuiQ charger. The yare about 5 years old and sat in storage for a couple of years. The batteries are able to charge to 100% as well as executing the equalization charge. It runs fine for about a mile or two and then goes into turtle mode (current limit mode). I think at least one of the batteries has gone bad. I will test with a load tester soon. Should I replace just the one battery of the others test good, or should I replace the entire pack? What are my options for replacing the battery pack with maintenance free batteries, either AGM or Gel? Any recommendations? Thanks in advance for any guidance.

Based on my experience with lead acid batteries, if they dried up during the time they were neglected- they are probably trash. It does sound as if one or more are bad. Did you check the electrolyte levels before charging? A load test or better a hygrometer to check charge states is needed. Oldhouseboater on this site has details on how to load test, search the forum.

Checking batteries is not that difficult. Charge the pack up to where it is happy and take a reading off each battery and note it’s voltage. They should all be very close to each other. Then take it for a run around a very short block (in your case).

Then take another survey. A weak battery will have a very different V. You may also have more than one.

Then do a load test and see how far they drop when using the car.

If they are 5 years old, and were severely discharged, they all will be bad. Some might quit in 1-2 miles and a few might make it to 5 miles. Changing 1 or 2 probably will give you little benefit. Either go with the cheaper wet batteries, like what is in there or lithium. Lithium is just a little more expensive then Gels but gives you significant performance gains, range and longevity. Especially in a 2005.

I also echo RD’s and LG’s thoughts [above]. I meant to include a bit more but got distracted by a squirrel.

You could keep the old Trojans around just to verify the systems are working and figuring out how you will use the car but you will always be struggling with “Range Anxiety” (its a real thing and not fun).

Depending on how much you have in the budget, You might also look into the new lithium solutions that are being presented by LG and Inwo today. There are many threads in the archives but the drop in 2 wire solutions are quite attractive to those not wanting to do a bunch of wiring.

They were almost dry. I am thinking they are trash as well but I will put them under a load tester and hygrometer today. Thanks for the response.

Thanks for the response. Can you give me a specific recommendation on lithium make/models #s to research? Also, will that require me to upgrade the Delta Q charger?

Neat stuff: Check either for current price and availability.

Thank you so much! I will investigate these options as they seem like a relatively simple upgrade. I am willing to spend the extra $$$ to get higher performance and no maintenance.

I have done a bunch of 2005, they are a little different. 2005 was the only year with the T3 controller. This controller can not be reprogrammed to make the motor turn higher RPM’s. Many spend the $ to upgrade to a T4. But there is another way to do it. The DC shunt motors in a Gem will also pull higher RPM’s if you raise their voltage, I wont bore you with the details on how it works but If we raise pack voltage , your motor will gain HP and RPM. Add that to lithium’s low voltage sag and you get good performance. Bottom line, lithium is great and lithium + higher voltage is even better(especially in a 2005).

Thank you so much. Please see my query on your Buy, Sell and Trade post and let me know how to proceed. Again, thanks for responding. I can’t wait to get the conversion going ASAP.

I have had good luck with the gel. I now have lithium but they have their quirks too. Like when they discharge to a low level they die and leave you on the side of the road. The charge level gauges don’t work very well on them, even ones that say for lithium batteries.

Hey Beachguy-
Tell me more about your system. Do you have a build thread I can go back and review?
What are you using for a BMS?

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I have an e4 with 4 yr old Trojans and not getting good mileage. I’m thinking of buying the Allied 12V 60ah Lithium Ion batteries ($285 ea). Anyone have any info on these? Any idea of what distance I could get with these on a full charge? Thanks.

Using 250 watts per mile = 18 miles.
Check the specs carefully. Can 6 be connected in series?
Can they supply 350+ amp peaks?
150 amp continuous?

IMHO-nothing good can come from 6 discrete bms in series.
Spend twice the money for twice the range and a single battery.

Haven’t seen any 72V lithiums. Are they available?

Here ya go.
Perfect for a Gem. $2500

Nice! Where can I buy?

Sorry, It looks like I missed this. Did not mean to ignore your Q.

We very recently had a guy (nfeenstra) post that he couldn’t get a set of Dakota packs to work right (after several months) and returned them all for a set of 72v 18Ah Allied. He was also having issues with the Allied set and several thoughts were thrown down and he has not reported back since.

As Inwo pointed out 60Ah might not get you very far, but more of an issue is that each battery might be a bit under rated in current flow for proper car operation. Also, each battery has it’s own internal BMS. In general, having multiple BMS units operating independent from each other is not a great scenario for our cars.


Nice! Where can I buy?

This is a pack that @Inwo and @LithiumGods are putting together as a drop in easy install, performance battery(stage 1 over volt?). It works quite well in 2005~2015 cars.

Placement of choice is the center section in between the frame uprights and spans across the two center battery trays and out the back of the car where the last two battery trays are under the spat.

The hardest part is calling on those high school woodshop classes and fabbing up a tray for the new pack to sit on. Mine looked something like this-

And snuggled into the tray nicely.

With battery slid in place.