Guide to reviving the Segway Gen 1 and Gen 2 battery

[TahoeJoe]

rene_canlas' guide worked on 3 out of 4 batteries for me! Thanks so much rene!

willballz11 (New Member) just posted another tip to try on another thread.. this would facilitate the same result without having to purchase an adjustable power supply.. he says:

I had a red light and a green light. Took the batteries off and tested voltage on both. One was 77v and one was 5v. So then I plugged in the Segway and tested the ports that the battery plug into. One read 27v. And the other read 11v. Not sure if that's a problem but it seems odd. Either way I used as heavy gauge wire as I could did negative to negative and positive to positive and let it sit for 40 seconds. Feeling both batteries the entire time and with a fire extinguisher nearby just in case. Neither battery heated up and when I tested batteries again the one that was at 5v was now reading 60v. So I plug in the two batteries on my Segway and Wala. Two green lights Segway recognizes both batteries now.

[dmurphy]

So now, I’m concerned.

Last year, my batteries dropped to about 50V as I recall, so I was able to trickle-float them back up and recover. Lesson learned about using a timer.

Well, this morning the Segway in my garage showed two red lights. They were both green short-flashing earlier in the week the last time the timer kicked on.

So I pulled the batteries and both are in the 68-69V range. Swapped them on the frame, and after about a minute, the two solid green lights go red. The rear first, and the front about 10 seconds later.

When I power the Segway on, all 5 top lights go red and I get the error beeps, with the exclamation point on the Infokey.

Any ideas how to troubleshoot this thing?

[TahoeJoe]

That happened to me too. After recovering 3 batteries, one of them went to red a few weeks later. I think it was due to not leaving the segway plugged in all of the time. I left it off charger for 48 hours, when I plugged back in, one of them turned to red within around 10 minutes.

I tried to trickle charge it back up again (twice), but it just never would turn green. My conclusion is that if you do manage to recover a battery, keep it plugged in and charging all the time after every ride. A recovered battery is an unstable battery and can go bad (turn red) at anytime. I don't think there is anything to troubleshoot here. Sorry man, recovered batteries are living on borrowed time

[dmurphy]

Originally Posted by TahoeJoe

That happened to me too. After recovering 3 batteries, one of them went to red a few weeks later. I think it was due to not leaving the segway plugged in all of the time. I left it off charger for 48 hours, when I plugged back in, one of them turned to red within around 10 minutes.

I tried to trickle charge it back up again (twice), but it just never would turn green. My conclusion is that if you do manage to recover a battery, keep it plugged in and charging all the time after every ride. A recovered battery is an unstable battery and can go bad (turn red) at anytime. I don't think there is anything to troubleshoot here. Sorry man, recovered batteries are living on borrowed time

So let me ask - what voltage were the batteries at when they went red? I’m still holding at ~70v, and I’m sure I could trickle them up even further. This almost feels like the charging board is locked up rather than the battery.

It’s been on a charger steadily all year. Had it on a timer as well so the charger would get “reset” once a week.

Either way, think it’s gotta go in for repair. Just hoping it’s the charging board and not the battery - a lot cheaper that way.

[TahoeJoe]

When mine went red they still would hold 70V too, but they still turned red. If the rene_canlas recovery method did not work for your battery, that means the cells are too far gone to revive. The next recovery method would be replacing the bad cells. That would move you over to this thread

Rebuilding Segway i2 battery
https://forums.segwaychat.org/showthread.php?t=36985

[dmurphy]

Originally Posted by TahoeJoe

When mine went red they still would hold 70V too, but they still turned red. If the rene_canlas recovery method did not work for your battery, that means the cells are too far gone to revive. The next recovery method would be replacing the bad cells. That would move you over to this thread

I let the battery packs sit disconnected for about 2 weeks. They continued to drain down to about 15V.

Then I put them on a DC power supply and very slowly brought them back up to 60V over the course of about 8 hours each.

Put them back on the Segway .... and ... we're back! All is good on the Western front.

Batteries charged up fully, went through cell balancing and now in trickle mode.

InfoKey is showing full charge, Segway rides great ...

I suspect (and it's just a guess) that either the charger or the in-battery BMS's locked up somewhere while it wasn't ridden.

That continual drain while disconnected leads me to think the BMS was doing something funky. But now we're all healthy it appears, so good to go!

[dmurphy]

So just for ha-has, I pulled the batteries back off. 78.5V each. Both holding solid.

I’m doing the “turn it on and lean against the wall” thing for a few hours and then we’ll recharge again. Make sure everything is copacetic.

But so far, looks good! Thanks Rene - this guide is worth its weight in gold!

[TahoeJoe]

That's awesome it worked! isnt it great to see both those lights go green, and stay green!

So what do you think you did different this time, than when you tried last time?

You said

almost feels like the charging board is locked up rather than the battery

.

Do you still think that? Or could it be the method, charge rate / time, amps?
You mentioned you let it charge for about 8 hours, thats alot longer than the 1 hour it typically takes with rene's method. Any idea how this time it worked over last?

[dmurphy]

Originally Posted by TahoeJoe

That's awesome it worked! isnt it great to see both those lights go green, and stay green!

So what do you think you did different this time, than when you tried last time?

You said .

Do you still think that? Or could it be the method, charge rate / time, amps?
You mentioned you let it charge for about 8 hours, thats alot longer than the 1 hour it typically takes with rene's method. Any idea how this time it worked over last?

It is great - and even better than the lights staying green was pulling them off and seeing 78V on the voltmeter! Whew. They’re charging well - only 3700 miles on them and 5 years old, so they should have plenty of life left.

The only thing I did differently was to wait until they really got low - down below 20V each. Then when I charged them back to 60V, I left them on the power supply for a while. I’m thinking something was up with the in battery controller - wonder at what voltage it shut down completely?

Maybe also leaving the i2 disconnected for a while reset the charging board....?

Either way, I’m feeling much better now. A little battery voodoo but the end result is good.

It’s funny - I also drive a Tesla, so lithium batteries and charging routines and such aren’t unfamiliar. I’m impressed with how far Tesla has come around battery technology. It’s genuinely years, if not decades ahead of the rest of the car industry.

[montejoe]

I tried this on a dead gen 1, was able to get both batteries charged enough to throw on unit. 1 battery was good the other was bad turns out. Thanks for the option though.