# New GEM Lithuim progress **URL:** \ **Category:** GEM Forum\ **Created:** [December 27, 2016, 1:18am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818 "2016-12-27T01:18:40Z")\ **Posts on this page:** 20\ **Page:** 7
**Author:** ![nakedwaterskier](https://avatars.discourse-cdn.com/v4/letter/n/258eb7/32.png) [@nakedwaterskier](https://community.electricforum.com/u/nakedwaterskier)\ **Post date:** [March 16, 2017, 5:40pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/123 "2017-03-16T17:40:35Z")
INFO FOR DEALING WITH ELCON: To ``` Electric Conversions ``` Message body I did not know how to figure amp hours. A friend finally emailed me the info. I attached his commentary at the bottom. CRITICAL INFO I PUT IN BOLDFACE SO YOU DON’T HAVE TO GO THROUGH IT ALL. And I shipped by USPS. Supposed to arrive to you tomorrow Saturday. Please let me know how and when to pay for the reprogramming. Thanks, Jeffrey Gillette [nakedwaterskier@yahoo.com](mailto:nakedwaterskier@yahoo.com) 5735 Melvin Ave Tarzana, CA 91356 8189160787 2002 Gem Car with Zivan Charger OEM BMS 24 [Chargery.com](http://Chargery.com) Battery Chemistry Lithium with lithium-manganese-oxide nickel oxide Cathode from 2013 Nissan Leaf Each Cell is rated at 32.5Ah OR 75V \* 65Ah = 4,875 Wh = 4.875kWh. (at Nominal see below) 20 Cells x 500W = 10 kWh Max. Cell Voltage 4.2V times 20 = 84V Nominal Cell Voltage 3.75V times 20 = 75V 20 Cells x 500W = 10 kWh USE ONLY 80% OF CAPACITY TO PRESERVE CYCLE LIFE SO MAX DESIRED CELL VOLTAGE: 4V times 20 = 80V CUT THAT TO 78V TO BE COMPATIBLE WITH GEM SYSTEM MAX CELL VOLTAGE 3.9V times 20 = 78V ## MIN CELL VOLTAGE 3.0V times 20 = 60V Please see boldface last paragraph below ## The Nissan Leaf battery pack is made of 192 Lithium-Ion (LiMnO2) cells, in a 96s2p configuration. Each cell is 32.5Ah @ 3.75V nominal, (3.2V - 4.2V). Four cells per module in a 2s2p configuration. And with 48 modules in the pack, this results in a 65Ah @ 360V. I am using 20. Per a Friend named David: Amp-hours add in parallel, voltage adds in series. Volts \* amps = watts which also means that Volts \* Amp-hours = Watt-hours. To estimate the kWh of a pack the nominal voltage is typically used though depending on the load the pack is under the actual amount of useable energy can be different. I assume you have **a string of 20 cell** **pairs meaning that you have a 2p20s arrangement. If this is the case** **you add the Ah of the 2 parallel cells and get 65Ah. Next you add the** **nominal voltage of the cells in series which gave you the 75V figure.** **75V \* 65Ah = 4,875 Wh = 4.875kWh.** **As for using only 80% of the cell capacity, the reserve should be at** **BOTH ends of the charge/discharge curve.** I don’t recall what Nissan uses for the top and bottom end but I would start with stopping when the cells are 95% full on charge and consider empty when there is 15% left at the bottom end. Also, if you can have a lower cutoff point for when you don’t need the full capacity then I would only charge to 80% for daily use. In fact, my Kia Soul EV cuts off at about 78% actual battery capacity when the dash says 80%. The dash only shows available capacity to the user not the actual battery capacity so the only way I know of to charge the battery over 95% actual SOC (state of charge) is to charge fully at the top of a hill and then regen down the hill. **It looks like your Gem system is calibrated to 78V target voltage.** **What I would do is charge to that point and then just before the** **charger shuts off adjust the voltage trim pot a little to raise the** **voltage a little at a time. If you turn the pot and the charger stops** **charging you probably turned the pot the wrong direction. If the** **charger shuts off before you are finished just restart it and it** **should cut back quickly so you can continue to adjust. If it is quiet** **enough and your hearing good enough you can hear a high pitched whine** **from the Zivan charger when it is charging. This whine will stop and** **start several times at the end of charge. This is when you want to** **adjust the voltage trim pot. Adjust a little at a time so you don’t go** **too far.** HTH, David ---
**Author:** ![Todd](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/todd/32/1061_2.png) [@Todd](https://community.electricforum.com/u/Todd)\ **Post date:** [March 17, 2017, 2:08pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/124 "2017-03-17T14:08:56Z")
> [@Inwo](#): > > That’s 4.15 per cell in your configuration, which is full up.Mike suggest a little lower for long life. No problem, I do 4.2 sometimes.You can do that by changing profile, or better yet, just set to 4.1 in BMS-24. > > ps.Get me the picture and I’ll help with the bms wires.I think Todd has the same. just 22s instead of 20s.He may have some tips. I’ve been using my cart the last week or so. It really seems to like the extra voltage that I’m getting out of the Leaf 11 modules. I installed a digital voltage meter on the dash so I can monitor the bank total voltage. I noticed that the factory dash battery monitor reads 100% charge till it hits 81.5V, then it drops off very quickly. At about 77V I get the -15 low voltage fault. I also have the spoof installed. Is there a way to lower the low voltage cut out? ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [March 17, 2017, 6:52pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/125 "2017-03-17T18:52:31Z")
Yes, try it without the spoof or a lower voltage one. What voltage is yours? Grant is getting a remote display perfected for the bms-24. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [March 17, 2017, 10:32pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/126 "2017-03-17T22:32:46Z")
Code 15 is fail to start. Won’t stop until key is turned off. 3.5v per cell is a good place for that. It keeps you from starting out with a dead battery. You can put a switch across the spoof (red to red) to limp home if you turn it off with a low battery. ---
**Author:** ![Todd](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/todd/32/1061_2.png) [@Todd](https://community.electricforum.com/u/Todd)\ **Post date:** [March 17, 2017, 11:13pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/127 "2017-03-17T23:13:42Z")
> [@Inwo](#): > > Code 15 is fail to start. Won’t stop until key is turned off. 3.5v per cell is a good place for that. It keeps you from starting out with a dead battery. > > You can put a switch across the spoof (red to red) to limp home if you turn it off with a low battery. The service manual that I have says that -15 is Low battery pack voltage. (less than 70 VDC). I think that I have a 6V spoof, so that’s pretty close since I got the -15 code at about 77V. I charge it to about 89.xx volts. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [March 18, 2017, 12:07am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/128 "2017-03-18T00:07:52Z")
What I mean is that if you are driving it doesn’t quit. Correct? That’s what my T4 does. If battery voltage is below 68.3 volts when key is turned on = -15. Usually happens to me when I come out of a store. I would be stranded if not for jumping the spoof. The 3.5v/cell is enough to get me home. I made up a 3v one for Mike. Lowering the low voltage cutoff will lower the high by same amount. I prefer the hard warning it keeps me from getting too low. ---
**Author:** ![Todd](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/todd/32/1061_2.png) [@Todd](https://community.electricforum.com/u/Todd)\ **Post date:** [March 19, 2017, 12:22am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/129 "2017-03-19T00:22:13Z")
> [@Inwo](#): > > What I mean is that if you are driving it doesn’t quit. Correct? That’s right, I think that I have a T2 and didn’t know the low voltage with the spoof, but learned quickly that when the BDI comes off of 100% it drops really quick. I’d better not turn of the key. Maybe I’ll install a switch in a desceret location to bypass the spoof. ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [March 19, 2017, 12:58am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/130 "2017-03-19T00:58:03Z")
Good idea. I haven’t had much feedback on spoof, so I don’t know what people need. The switch will work either way. Turn it off to start car with high voltage, or on to start with low voltage. A momentary button might be best. When you are stranded, push the button to start. ---
**Author:** ![Todd](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/todd/32/1061_2.png) [@Todd](https://community.electricforum.com/u/Todd)\ **Post date:** [March 20, 2017, 10:48pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/131 "2017-03-20T22:48:19Z")
> [@Inwo](#): > > A momentary button might be best. When you are stranded, push the button to start. That’s exactly what I had in mind. 😉 ---
**Author:** ![Jeffrey\_Gillette](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/jeffrey_gillette/32/791_2.png) [@Jeffrey\_Gillette](https://community.electricforum.com/u/Jeffrey_Gillette)\ **Post date:** [April 1, 2017, 8:27pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/132 "2017-04-01T20:27:40Z")
Evidently my GEM oem low voltage warning buzzer now comes on early. Also with my Blue BMS24 on dash, don’t really need over discharge cutoff relay ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [January 7, 2018, 7:07am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/133 "2018-01-07T07:07:24Z")
Lots of pictures and good information here. A T2 that seems to work with voltage spoof. Cutting Volt battery water jackets. ---
**Author:** ![hazed](https://avatars.discourse-cdn.com/v4/letter/h/c6cbf5/32.png) [@hazed](https://community.electricforum.com/u/hazed)\ **Post date:** [July 19, 2018, 2:20am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/134 "2018-07-19T02:20:04Z")
Understanding this thread is a little old, it seemed appropriate for my question. I have a 2001 Zivan NG1 charger that was micro-upgraded at some point. So, when doing a lithium conversion to 84v, is it better to send that off to get it modified to charge lithiums or is money better spent buying a new charger and selling the old Zivan? ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [July 19, 2018, 3:47am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/135 "2018-07-19T03:47:41Z")
I’d recommend the dq. But I’m far from unbiased. I’ve never seen a zivan, and deal in new an used dq. As I recall, most of the lithium conversions ended up with dq chargers. For reference, a new dq is $350. Used if available, $250. I don’t know what you could get for the zivan. ---
**Author:** ![hazed](https://avatars.discourse-cdn.com/v4/letter/h/c6cbf5/32.png) [@hazed](https://community.electricforum.com/u/hazed)\ **Post date:** [July 19, 2018, 4:21pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/136 "2018-07-19T16:21:29Z")
Do you typically have new and used dq chargers on hand, programmed for lithium? I will probably need a couple of your other items you list for the conversion as well! ---
**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\ **Post date:** [July 19, 2018, 4:26pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/137 "2018-07-19T16:26:12Z")
I sold my last used dq, but have new. I can program to the needed lithium profile. ---
**Author:** ![Todd](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/todd/32/1061_2.png) [@Todd](https://community.electricforum.com/u/Todd)\ **Post date:** [August 15, 2018, 12:13am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/138 "2018-08-15T00:13:44Z")
I had my Zivan reprogrammed for 90 volt lithium upgrade. I think that it was around $95 and took a couple weeks. Two years later it is performing as it should. ---
**Author:** ![BadBrad](https://avatars.discourse-cdn.com/v4/letter/b/e47774/32.png) [@BadBrad](https://community.electricforum.com/u/BadBrad)\ **Post date:** [November 16, 2018, 6:03am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/139 "2018-11-16T06:03:42Z")
Do you have any pictures? Looking to do this soon. ---
**Author:** ![BadBrad](https://avatars.discourse-cdn.com/v4/letter/b/e47774/32.png) [@BadBrad](https://community.electricforum.com/u/BadBrad)\ **Post date:** [November 16, 2018, 6:08am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/140 "2018-11-16T06:08:04Z")
Sorry I thought that would go under his comment. I’m looking for ways you can raise the GEM car. Pictures would be great. I have a 2003 2 passenger. ---
**Author:** ![chris1](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/chris1/32/3300_2.png) [@chris1](https://community.electricforum.com/u/chris1)\ **Post date:** [November 16, 2018, 2:42pm UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/141 "2018-11-16T14:42:47Z")
Im lifting my 2002 4 seater now. The rear end is finished, here is how I did it. Im almost up to the front end. I used 3/16" stainless. When I am finished I will create a thread with sketchup files. ![IMG_2922](https://canada1.discourse-cdn.com/flex030/uploads/electricforum/original/2X/7/79e02a9609d9e2aefca94663fe06999c386d7d0d.jpeg) ![rear%20shock%20mount](https://canada1.discourse-cdn.com/flex030/uploads/electricforum/original/2X/a/ae58561cb710641fec22ae78d597908169c22196.jpeg) ---
**Author:** ![dougl](https://avatars.discourse-cdn.com/v4/letter/d/b19c9b/32.png) [@dougl](https://community.electricforum.com/u/dougl)\ **Post date:** [November 17, 2018, 5:19am UTC](https://community.electricforum.com/t/new-gem-lithuim-progress/11818/142 "2018-11-17T05:19:08Z")
@Todd is it fixed at 90V for Lithium and specified by you when sent in or is there any way to adjust the top voltage? I’m getting 5 new Nissan Leaf Gen 4 battery modules( 20S ) with 4.1V set at the top, that’s 82V but at some point I might add a half module(2S) which would mean either sending it in again for the firmware update for 90V or hopefully turning a knob, or setting some jumpers or switches. [Previous page](https://community.electricforum.com/t/new-gem-lithuim-progress/11818.md?page=6) [Next page](https://community.electricforum.com/t/new-gem-lithuim-progress/11818.md?page=8)