Yes, we can do that privately.
I have a head start on cell testing. One module is finishing now. Two more are charged and ready for discharge test. It also helps not needing to recharge to storage level. I need them all empty when I charge them in series.
#4 18 cells will be fine.
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Almost there.
Notice the module to module jumpers. Removed for shipping.
Just need to do a test charge.
Charging at 10a. Should finish in 7 hrs.
Thanks for the update.
Do you have any recommendations for temperature monitoring or spacing (air circulation) between modules?
Other than taking a voltmeter to each cell, what about small gage wires from each cell to a terminal strip? Would an Arduino or other microcontroller be suitable as a voltage monitor?
Temperature won’t be an issue slow charging at less than 20a.
I’m making final test now. Cells a staying within 20mv. Actually much closer, as only 1 cell is 20mv high.
Even though, I said “no bms needed”, a voltage monitor is priceless.
Do you have something android to monitor with bluetooth?
I’ll send a bluetooth board along, and an android tablet too, if not.
It will help with your review of the system. Keep the wiring, and send back board when through testing.
The main point of this battery is keeping it simple, but I would like you to keep an eye on performance, it being the first one.
There are 26 wires. B- and 1 wire to + on each of 25 cells.
I’m excited! 
This is like my child. I’ve been working on it for weeks.
On the final, I hope, charge cycle.
I’ll be up til midnight, looks like.
All 30cells being charged in 30s.
From dead, 2.8v, to 100.8v/30 took 28.039ah.
Voltage has changed little in the last 5ah. These cells hold a steady voltage.
What I’m looking for is charger turning off without a cell going high. If it does that, it’s good to go with no bms.
ps.
Disregard the 28s setting of charger. C10325 will only do 28 lfp cells. So I fooled it by setting cell voltage higher!
I am all for voltage monitoring, data logging. Your bluetooth board, great! I don’t have anything android, will invest as needed, suggestions?
I just picked up a new rca tablet for $35.
Mainly use this Galaxy.
Bluetooth is always buggy for me, but that may be because I switch from device to device.
Vbms app is available from the play store. If you find an android, search for it.
Need your UPS shipping address.
20400 Baywater Road
Tavares Florida
32778
Do I have something coming?
Are you interested in a 2016 GEM AC Motor. I have a take out that has a vibration.
In a message dated 9/20/2018 10:45:57 AM US Eastern Standard Time, electricforum@discoursemail.com writes:
September 20
Need your UPS shipping address.
Sorry, meant @stretchkart .
I’ll send you something if you feel left out.
I have a vibrating ac motor from another source. tnx though.
That project is on the back burner while I test batteries.
Dave,
I think I’ve located an android device for VBMS app. Do I need a shunt to measure amps? I think I want one anyway. Do you have any experience with the hall effect type?
Only that they need power. But the bluetooth would in any case.
What is it your trying to do?
I use the wireless model meter that looks similar.
The vbms bms is bluetooth and has a companion lcd.(wired)
So, will this lcd work with bms?
Or is it just a bluetooth meter?
Bluetooth sucks IMO.
I think is just a meter.
I would like to known amps flowing in and out of the pack. Watts used per unit of distance etc.
As for SOC for the pack is, monitoring voltage sufficient? The voltage curve is pretty flat with this type of cell right?
Should work good for that. That’s what I used before I found the bms monitor.
Michael is using one too.
Thanks,
They seem to come in capacities ranging from 50 to 500 amps. I’m wondering if one that is rated at 500 amps will be less accurate at say 10 to 20 amps ( what I imagine will be an average amp draw in cruise). What max amperage meter would you recommend?
I usually use 300amp for that reason. A gem rarely exceeds 300a. Although I did trip out bms today running 30mph uphill. It’s so rare that I’m surprised when it happens. If I watch the ammeter, there is never a need for 300a. It only wastes juice.
I use < 50amps at steady 25mph.
LIF battery voltage drops when empty and rises when full. In the middle, it’s difficult to gauge soc.
The ah meter should help a lot.
If you look at the specs, a single 60a cell is 180a continuous, 300a for 30 seconds.
A Gem will work a single set hard if hot-rodding.
Within specs though.
I’ve been running a double set on 48v cars. 2p16s. But then a 48v will draw more current.
@LithiumGods got 23 miles with 60ah. I never do, but my trips are less that a mile and uphill both ways. 
Thanks for the spec sheet.
How should my DQ charger be set up?