Looks good with two buts. One is leaving a bit of an air gap between top/bottom batteries for cooling and another is that it does not look rain or wash worthy.
Thanks, yes there is about a half inch of a air gap from the bottom battery to the top battery. I was thinking about the wash and rain today on how to box it in or add an extended rubber flap to keep the water off. That is something if you or anyone has a good idea I would like to hear. I still need to get to the BMS to charge the batteries so still need some access.
Thanks for the reply
I personally don’t think Battery cooling is a issue. The most I have EVER seen from my car is a 260Amp draw at take off and then down to around 200-150 amps on a regular heavy pull. So I don’t think Gems can pull that much power to cause a hot battery. But it would be a good idea to keep a eye on it. Tyson’s Battery has a Temp sense on it where he can see the battery’s temp on the Dash via the BMS so it will be cool for him to report back Battery temps as he drives. Example you can see on the lower right hand side of the BMS display his battery is 67 degrees right now.
I would get a piece of sheet rubber and attach it to the underside of the front window and drape it across the front of The battery. That will keep everything pretty rain free.
Ya, I see the sensor taped to the top of the top battery. Basically in the place where it would be the coolest. I would have put it in the middle or back of the bottom battery between the two batteries.
I don’t yet know how these batteries deal with heat and some long hills might cause some warming. Would like to know more for sure. And that’s a nice BMS and charging system.
I can unscrew the top battery and move that temp sensor to the bottoms battery so it is in between the batteries to get a better reading. I will work on that tomorrow. The temp outside today was 50 in Ohio. So doing a test drive today wasn’t ideal. I have a short day at work tomorrow and plan on bring the gem home on Thursday for a long test run to see how it handles and runs
I will report back on some good numbers as I should be able to drive the gem to my kids soccer practice on Thursday which is 5 miles away and driving on 35 mile roads.
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Zero worry about battery generated heat. The puny little gem motor will melt before battery goes over ambient. 
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After a week of playing around on the Gem, This thing has so much power. I am hitting 40 no problem on flat and slight downhill, uphill I can hit 35 from dead stop. I haven’t hit that hill with speed yet but will here soon. I have the controller set to cut off at 40 I know I can get more out of this but breaking is a concern. Lithium is the way to go if you want power, I have been driving about 10 miles at a time to and from kids soccer practice and still have plenty of juice left to probably go another 10 miles.
However I need to figure out how to get my Regain to kick in more when I let off the throttle. Marlon back in 2012 helped me reprogram the Gem and now I would like the Regain to help with the breaking. I have a Handheld programmer I just need to know what field the Regain is on a 2002 so I can turn it up a little at a time till I get the right amount. I have search the forum and saw people asking the same question but never seen the final answer.
Tyson after 10 miles what’s your voltage?
3.9? 3.8?
I have found that you have lots of power between 3.8 & 3.5 slowly test out your range you will be surprised at how far you can go on 12k of power. I would bet your car in it’s current configuration is a 35+ mile car. My car will go that far with the big wheels and mountain goat hills
BTW you are only 1 of 5 cars I know of that have this kind of power. And 1 of only 2 cars I know of that have your exact set up.
Might be soc indicator.
@grantwest, how does your soc work?
20s I’m testing shows 11% at >3.7v.
Temp sensor connected.
Does it work from AH? Meaning that shunt must be connected properly and soc goes up with wh put in.
I’ll soon know. Jason keeps messing with fw.
He never put in our big ammeter screen either.
Hey! I believe I know how to fool wh reading to speed up my testing.
I’m telling bms that I’m charging at 100a. (68a shown)
Wh should come up fast. It needs a preset in menu.
Or is there? I’ll look.
That was my next thing. The SOC at 3.9 is at like 3/4 over and when I get down to 3.7ish it is in the yellow. I had a bunch of kids on it and really wasn’t paying that much attention to the SOC my son was the one that pointed it out that I had only half charge left. I knew since it read 3.7 I had plenty to go from @grantwest I will test more this weekend and report on SOC. My WH still says 0.00… Do I have that wired wrong? when I drive it does read -##Amps while moving? my Regain does not kick in at all which I really want to happen to help slow down.
Shunt wires might be backwards. WH can’t go below zero.
Run battery empty. <3.5v.
Connect charger and watch wh go up.
Should take ~8,000-10,000wh.
every 250wh should be 1 mile range.
ps.
Is charger connected opposite battery on shunt?
Shunt Ground is on the same Terminal as Chargery Charger.
ON the shunt, I have the Red wire on Battery Side and Black Wire on Controller Side.
the WH reads 0.0 all the time.
Sounds correct.
Nothing connects to battery side of shunt except small red sense wire.
That is how I have it connected. just how grant said, is that not correct?
as you can see in the first 10 sec, he said to hook the pos and neg right on with the charger?
#1 don’t worry about splitting your pack to relocate the temp. I agree Zero worry’s about heat.
#2 just switch the black and red wires on the shunt. No worry’s about breaking anything you can do it hot. One way the BMS will read - when your pulling amps and it will just say a number when your charging or in re gen.
Don’t pay attention to the rainbow gauge it’s in accurate. Pay only attention to the cell voltage. And you can only tell the cells voltage when the car is stopped . Again it’s in accurate when the power is being drawn
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I will switch the Red and Black wires on the shunt and see if that makes a difference. Should the Amps be negative when driving? or positive. To me I would expect them to read neg since it is pulling out?
I have the Neg cable wire going to the shunt over top the Neg Charging wire. is this correct or do I need to change the charging wires around?
on top of the shunt I have the Red wire on the side of the Battery and the Black wire on the side of the controller.
