# Gem lithium ion conversion help **URL:** \ **Category:** GEM Forum\ **Created:** [March 24, 2022, 7:48pm UTC](https://community.electricforum.com/t/gem-lithium-ion-conversion-help/23794 "2022-03-24T19:48:14Z")\ **Posts on this page:** 1\ **Showing post:** 21
**Author:** ![JarJarJava](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/jarjarjava/32/15158_2.png) [@JarJarJava](https://community.electricforum.com/u/JarJarJava)\ **Post date:** [May 1, 2022, 12:57am UTC](https://community.electricforum.com/t/gem-lithium-ion-conversion-help/23794/21 "2022-05-01T00:57:52Z")
> [@barry1](#): > > OK Thank you. The guy at R4F said I could send my charger in to reprogram but he would need the exact specs on the battties so the reprogram whould be right. Based on the mailing back and forth, his rebuild,and cost I think he felt it best to just go with the charger that comes with the batteries. I assumed he ment the charger that comes with somrthing like battle born or big battery, something like that where it is drop in ready. The R$4 SuperCharger is northing more than a rebranded Quick Charge corp Select-A-Charge SCO7210. The F5 profile, which is the lithium profile, needs to be factory programmed because they want to set the max voltage to match the number of cells in your pack. F5 was originally intended for LiFePo4 cells, which only go to 3.6v / cell whereas the SDI cells are a different chemistry and go to 4.1v. It’s a brute force, old school, dumb as box of rocks, wound transformer based charger - I have no idea how F5 might interplay on a different lithium chemistry. As @Inwo might have told you, you are probably better off with one of the lead profiles. Now, I see you have Trojan XHS30 batteries in there. If configured correctly, this should put the charger on F3-d2. F3 is the 3-stage deep cycle program, and d2 lengthens the cycle and I believe raises the voltages. It’s the modifier for the “BIG” batteries: Trojans, Full River, US Battery for example. You might need to change the “d” profile. Not sure if F should be changed to something like F2 (2-stage) or F4 (AGM - which on this charger has a flatter curve). - that’s a @Inwo or @LithiumGods question that I can’t answer. Changing profiles is super easy, here’s the manual, and they also put a youtube video out. You power it up without the batteries connected and it goes into programming mode. Then its just pushing buttons on the front. Here’s all the documentation that they scattered around their website: - Operating manual: [https://www.quickcharge.com/standard%20portable%20chargers\_htm\_files/SCO%20charger%20Instructions.pdf](https://www.quickcharge.com/standard%20portable%20chargers_htm_files/SCO%20charger%20Instructions.pdf) - Tech product cut sheet: [https://www.quickcharge.com/standard%20portable%20chargers\_htm\_files/SCO%20lit..pdf](https://www.quickcharge.com/standard%20portable%20chargers_htm_files/SCO%20lit..pdf) - Charge curves for various profiles: [https://www.quickcharge.com/standard%20portable%20chargers\_htm\_files/charge%20curves.pdf](https://www.quickcharge.com/standard%20portable%20chargers_htm_files/charge%20curves.pdf) - FAQ, they talk about F5 about 3/4 of the way down [Quick Charge Corp. Battery Chargers](https://www.quickcharge.com/service%20faq-a.htm) - Product page: [select-a-charge on board battery chargers](https://www.quickcharge.com/select-a-charge%20on%20boards.htm) --- _[View the full topic](https://community.electricforum.com/t/gem-lithium-ion-conversion-help/23794)._