Revive Three Segways! Dying batteries

[sanfairyanne]

I have been asked to explore the possibility of reviving the batteries from three Segways which have been left for one year. They were stored with full batteries but have not had top ups.
I found some info' for a company in Australia that specializes in reviving Segway batteries but we are in Holland and unable to surface mail our lithium batteries.

We our getting this light sequence:

Segway one: solid red light, flashing green light
Segway two: single flashing green light
Segway three: single flashing green light

I wondered if anyone knows of a company in Europe that can revive (or attempt to revive Segway Lithium batteries.

Many thanks in advance.

[ions82]

From what I understand, reviving batteries is simply a matter of bringing the pack voltage above the LVC (low voltage cut-off) by supplying voltage to the main battery terminals. If the pack voltage can be raised above the LVC, the on-board charging and battery management system will then charge and balance the pack as needed. It's not a terribly complicated process, but caution needs to be exercised, and it helps to have an understanding of the theories involved with balancing lithium battery packs.

[MTOBATTERY]

In the ideal world you would be correct. If that is done and there is failed cells within the pack there can very easily be a fire. You also risk potential damage to the BMS depending upon how you accomplish this task.

SanFairyAnne, please email [email protected] regarding this need. We have a few customers in Europe with our lithium battery reconditioners. We would be happy to introduce you to them.

[Don M]

Originally Posted by MTOBATTERY

In the ideal world you would be correct. If that is done and there is failed cells within the pack there can very easily be a fire.

I'm curious. With all the hoopla going around right now about Lithiums catching fire and burning down houses and cars, has there ever been a documented case of a Segway battery actually catching fire? Got a link to an article about it?

I own two electric cars with Lithium power and I know car makers have gone to extraordinary lengths to make sure their batteries don't catch fire as that could very easily burn down your house if they are stored in a connected garage. Segways are probably stored indoors 95% of the time too - Has a Segway ever burned down a house? Seg batteries seem to be engineered with safety as the #1 priority - I know it's easily possible to get at least twice the power from the 18650 form factor batteries that they use, but it appears Segway resisted the temptation to go for the extra power/range in favor of building a nearly bullet-proof battery pack. If only they had incorporated an On/Off switch so you could store the machine for a year or two without needing to plug it in. My electric car can sit at 1/4 charge for two or three years if need be without harm - They actually recommend having the battery at 1/3rd to 1/4 charge if you're going to leave it sit for extended periods

Don

[ions82]

I've wondered the same thing. I think it is highly unlikely the Seg batteries would catch fire. They are, literally, "bulletproof." I remember a Valence Saphion promo video where they shot the cells with a gun. No fire. Regular lithiums burst into flames. So, I'd feel OK in using the voltage supply trick on a pack that still has Saphion cells, but I wouldn't be as confident If trying it with a rebuilt pack. Some accounts I read in which individuals revived their own packs said it only took a matter of minutes of supplying voltage to a dead pack (showing less than 10 volts) to bring it back up to a "chargeable" state.

Also, as Jason from MTO mentioned, even successfully reviving a pack doesn't mean that it doesn't have bad or degraded cells. It may have a couple bad ones but is still perfectly useable. For how long becomes the question. It's amazing that a lot of these Segway packs that are ten years old are still kicking. It's a testament to how well the cells and BMS are engineered. But as Don mentioned, the only way to store the Seg unplugged is to remove the batteries. Otherwise, they risk that early/untimely death.

[sanfairyanne]

Thanks for all the useful information. I passed it on to my employer and expect them to seek a revival service from a Dutch Segway retailer.

[MTOBATTERY]

I know a gentleman in Maryland who had his P-133 literally blow up when he unplugged his seg. The NiMH cells vented while charging and the gases built up inside the base. When he unplugged the cord from the csb he got that small spark that we have probably all noticed and it ignited the gases. (Special note: these were not rebuilt batteries). The platform was bulged upward a few inches upward from the pressure that built up inside the base and of course nearly everything was a loss on the Seg. Bottom line, it's possible with any battery chemistry. Nobody ever wants to experience it or hear it but it does happen.

[MTOBATTERY]

Originally Posted by ions82

I've wondered the same thing. I think it is highly unlikely the Seg batteries would catch fire. They are, literally, "bulletproof." I remember a Valence Saphion promo video where they shot the cells with a gun. No fire. Regular lithiums burst into flames. So, I'd feel OK in using the voltage supply trick on a pack that still has Saphion cells, but I wouldn't be as confident If trying it with a rebuilt pack. Some accounts I read in which individuals revived their own packs said it only took a matter of minutes of supplying voltage to a dead pack (showing less than 10 volts) to bring it back up to a "chargeable" state.

Also, as Jason from MTO mentioned, even successfully reviving a pack doesn't mean that it doesn't have bad or degraded cells. It may have a couple bad ones but is still perfectly useable. For how long becomes the question. It's amazing that a lot of these Segway packs that are ten years old are still kicking. It's a testament to how well the cells and BMS are engineered. But as Don mentioned, the only way to store the Seg unplugged is to remove the batteries. Otherwise, they risk that early/untimely death.

I remember that video. What everyone shoudl consider is that Saphion is just a brand of lithium iron phosphate battery. It is no different than Coke being a soda. In fact, any UN38.3 tested/approved lithium iron phosphate battery will do exactly what you saw in the video. Our rebuilds react the same if punctured. In the end Saphion cells aren't any safer than the ones we use in rebuilds but rather it is a name that was marketed quite well. Lithium iron phosphate is certainly a "safer" chemistry of lithium than lithium cobalt or lithium manganese etc..

I also wanted to clarify my statement since your reply made me question whether I was clear enough in what I wrote. "Even successfully reviving a pack doesn't mean that it doesn't have bad or degraded cells". That part I agree with. I do not agree that a pack with a few bad cells is perfectly usable or safe. In many cases the BMS would restrict use based upon dead/inferior cells. Be well!