Charging Balance Problems

[Crowe5612@gmail.com]

Hello, I have searched through the forums but haven't found an answer yet and I really don't have time so I hope you all can help.
This is the first time Ive seen this, New Build, after a couple days of use cells read while charging 1-3.85 2-3.8 3-3.75 and never fully balance out. Full Charge 1-4.21 2-4.16 3-4.11
after a couple weeks the pack took a dump.

Replaced battery with a fully tested, known working and perfectly balanced battery, after 3 days its doing the same thing. Not my mod, a customers. Is there a possibility this is something they are causing or an issue with the board? I really don't like RMAing boards to evolv if I can help it.

Thank you

[BillW50]

Are those voltage readings from EScribe or from a multimeter? As when the DNA is working flawlessly, I trust its cell voltages. But if I suspect something is wrong with the DNA, even the slightest, I wouldn't trust those readings in a second.

[retird]

I guess you built the mod for the customer???? Did you use the Production Utility?

If you did how did you set up the mod using the Production Utility. What was the Maximum Cell Imbalance  maximum voltage variance set at for the test. What did the test show? 

If you have the production file used to configure the device you can run a test in the utility...

At any rate there can be many reasons for what you are seeing.  Cold solder joints at the balancing connectors/wires, poor grounds, less than good quality batteries, cell soft cutoff to low,  and etc.  If the board is charging properly then I doubt that it's the issue especially if it charges to 4.20 volts which it is doing @ 4.21 volts in your info to us...sometimes it takes several charges on a new battery to settle down... 

If the build is solid and battery is rock solid good ( when charged with an external balancing charger) I guess a RMA would let Evolv look at the board....

[retird]

Oh.... do we know if the customer has changed anything?  Have you tried Restoring to Default if changes have been made by the customer?  

[Crowe5612@gmail.com]

Thank you, yes it was setup using production utility. Imbalance was set to .15 maximum.

The battery I installed the second go was out of my own personal mod and has never been out more than .02, that being said. I charged the battery with an external charger a few minutes ago and it rebalanced correctly.
Out of 156 production units this is the first time ive seen this and it not jsut being a simple bad battery. So it raised the question, even for future reference. Is there something that people do that causes the cells to get that far out of whack.... personally there is a pack in my prototype that is almost a year old, first gen 200 and still works flawlessly. So I'm not sure what to think when I see people have issues with batteries.

anyway, boards out and I will cleanup and resolder the balance connector JIC Hopefully that's it. Thank you and Ill let you know what happens

[retird]

Great comments....

Since you ran Production Utility when setting up this mod I guess you could configure it again.  Should there have been a user induced issue (not saying there is/was) but just covers one piece of the pie... then you can see if it balances any differently...

Best thoughts I have... troubleshooting blindly is iffy at best... ya know what I mean???

Good luck..  let us know what ya find out...