Jump to content

Ninebot One P battery failure & crash


Cranium
 Share

Recommended Posts

32 minutes ago, Cranium said:

Now I have a decision to make. 

  1. Do I buy a new battery? 
  2. Do I build a new pack myself (kind of itching to do this)? 
  3. Do I buy a new EUC and just sell this one off for parts? 
  4. Or maybe I buy a new EUC and make a new battery?

 

Ouch! Glad you weren't seriously hurt. As for the four options, batteries are still too expensive, and sourcing the 340Wh P battery from anywhere other than NinebotUS or SpeedyFeet will be very difficult. I paid only $150 for my 320Wh E+ batteries last year, but the batteries are all gone and not rated for the P. 

If it were me, I would buy a new EUC (Ninebot Z or other more powerful wheel) and keep the P for a project/back-up wheel, and build a new battery pack using cell loggers instead of BMS (see this thread posted previously), but I still have too many other issues to sort out for now.

Edited by litewave
Link to comment
Share on other sites

1 hour ago, Cranium said:

  I never did get any x-rays to see if there was a break but there isn't any discoloration so I'm assuming it isn't broken.

My wrist (scaphoid bone) was broken, and there was no discoloration, just some mild swelling and pain. The way you landed on the heel of your palm is the classic way to break the scaphoid. 

Please reconsider and see a hand specialist to have x-rays done for a proper diagnosis. If you wait like I did, surgery is in your future. The alternative to treatment is potentially a lifetime of arthritis in that hand.

Link to comment
Share on other sites

9 minutes ago, dbfrese said:

My wrist (scaphoid bone) was broken, and there was no discoloration, just some mild swelling and pain. The way you landed on the heel of your palm is the classic way to break the scaphoid. 

Please reconsider and see a hand specialist to have x-rays done for a proper diagnosis. If you wait like I did, surgery is in your future. The alternative to treatment is potentially a lifetime of arthritis in that hand.

Thanks for sharing this.  I'm a bit more concerned now.  lol.  The soreness/tenderness I have is on the outside of the wrist below the pinky so while it wouldn't be the scaphoid I guess it could be one of the other bones in there.  But I'm going to go have it checked out just to be sure there isn't something wrong though.

Link to comment
Share on other sites

1 hour ago, LanghamP said:

What's the easiest way for a newbie like me to find out the health of all the battery cells on all my wheels?

The easiest way I can think of is to do a range test and track how many miles you get before you start getting low battery alarms.  If the range is a lot lower than expected or you see a drop over time then it is time to take the next step to check the individual cell voltages which would require opening up the battery and checking with a multi-meter.

  • Upvote 2
Link to comment
Share on other sites

15 hours ago, dbfrese said:

My wrist (scaphoid bone) was broken, and there was no discoloration, just some mild swelling and pain. The way you landed on the heel of your palm is the classic way to break the scaphoid. 

Please reconsider and see a hand specialist to have x-rays done for a proper diagnosis. If you wait like I did, surgery is in your future. The alternative to treatment is potentially a lifetime of arthritis in that hand.

+1 on that.  I think you broke something too. One month is too long for pain without ongoing injury. Check it ASAP.  At least you will know. A simple, inexpensive x-Ray should do.  They're free here, not sure there.

im not going to lecture you on the value of wrist guards, you found out the hard way, and I'm sorry for your pain.

Link to comment
Share on other sites

Just now, Smoother said:

im not going to lecture you on the value of wrist guards, you found out the hard way, and I'm sorry for your pain.

My wrist guards were in my backpack with my laptop.  I made a conscious decision to not put them on because it was a very short, familiar trip where I knew there would be no unexpected obstacles and I wasn't pushing speeds.  Good thing too because they would have gotten all scratched up if I had them on.  ;)  I did have my helmet on at the time so I wasn't a complete dumbass.  

I relaxed my safety precautions and it cost me.  Good ole Murphy's law!

Link to comment
Share on other sites

9 minutes ago, Cranium said:

I relaxed my safety precautions and it cost me.  Good ole Murphy's law!

Indeed. But you forgot the elephant in the room, or to more precise, between your legs ( that sounded a bit naughty, didn't it!) the "no fail-safe" self balancing bomb. Tick tick tick tick BOOM!!!

glad to hear you didn't get your sense of humour knocked out in the fall.

about batteries, dig those two cells out and rebuild  that puppy, you're dying to have a go.

Link to comment
Share on other sites

47 minutes ago, Cranium said:

I relaxed my safety precautions and it cost me.  Good ole Murphy's law!

there we go, I knew there had to be an advantage to never wear protection gear :)

I agree with the previous posters, lack of discoloration is not a way to rule out a fracture, it's rather making 2 x-rays. A month is a long time for pain, yet that's not a way to diagnose a fracture either.

Edited by Mono
Link to comment
Share on other sites

19 hours ago, Cranium said:

Both hands were chewed up pretty good.  My right arm had some good road rash.  Both knees had road rash. 

I feel your pain, quite literally! In late 2015 I was doing a range test with an early version of the MCM4, it was the morning after a Christmas party... was feeling muddle headed, forgot my wrist-guards, the Wheel cut-out into 11kph (total mileage) when ridding 25kph with the limiter off. It took a good 3 months before the pain properly subsided. This was the school of hard-knocks lesson to inculcate a fanatical observance in use of wearing wrist-guards; it's now become a ritual, even before turning on the machine, I'll have the guards fitted—it's the reason why we supply them with every Wheel purchase now.

 

uc?export=view&id=11SHXyNK4aWKJgbDvGY7bQ

Edited by Jason McNeil
  • Like 2
  • Upvote 1
Link to comment
Share on other sites

1 hour ago, Jason McNeil said:

I feel your pain, quite literally! In late 2015 I was doing a range test with an early version of the MCM4, it was the morning after a Christmas party... was feeling muddle headed, forgot my wrist-guards, the Wheel cut-out into 11kph (total mileage) when ridding 25kph with the limiter off. It took a good 3 month before the pain properly subsided. This was the school of hard-knocks lesson to inculcate a fanatical observance in use of wearing wrist-guards; it's now become a ritual, even before turning on the machine, I'll have the guards fitted—it's the reason why we supply them with every Wheel purchase now.

My hands looked just like yours.  I'll be getting another set of wrist guards when I get my KS 16S from you.  :)   And I won't keep them in my backpack anymore even on short rides!

  • Like 1
Link to comment
Share on other sites

It's Funny ( not really, but @LanghamP made it so I can't use "ironic" anymore) when I was reading @Jason McNeil post from 2015, you @Cranium responded on page 2 I think.  It's all gone around in a bit of a circle.  Like I said, no lecture here, just an interesting discovery.

@Jason McNeil, how long was it before your hands were normal again, or are there still lingering effects? 

Link to comment
Share on other sites

11 hours ago, Smoother said:

@Jason McNeil, how long was it before your hands were normal again, or are there still lingering effects? 

Now,  pretty much normal, there's a 3mm lump of scar tissue, but that's about it.

Like most probably everyone else, I've had a couple bad injuries earlier in life, but for medium-low level constant pain, broken bones are as nothing to the skin being ripped of your wrists.
The nerve density map of the brain gives an indication how many nerve receptors will be giving notice of protest for months to come.

main-qimg-7923275e8ee899b09bb2e072a787b4

Edited by Jason McNeil
Link to comment
Share on other sites

12 minutes ago, Jason McNeil said:

Like probably most everyone else, I've had a couple bad injuries earlier in life,  broken bones are as nothing to the skin being ripped of your wrists.
The nerve density map of the brain (picture of me on a good day:P) gives an indication how many nerve receptors will be giving notice of protest for months to come.

main-qimg-7923275e8ee899b09bb2e072a787b4

Based on that image and the chart on the left, it looks like you could take a swift kick to the plums and not even blink.  Respect ;)

actually, looking at those lips, no wonder it was so painful to ride a motorbike without a face shield, in the rain.  Every raindrop on the lips felt like a BB fired at close range.

Edited by Smoother
Link to comment
Share on other sites

22 hours ago, Cranium said:

  The ride is mostly on a concrete walkway with the beginning and end being on asphalt.  About 1/2 way there while on a straightaway and going somewhere in the neighborhood of 10-15MPH, the Ninebot just died

This link for related 'unexpected power off' crash reports has several reports like yours.

forum.electricunicycle.org/topic/1376-ninebot-one-shutting-off-while-riding/.30
 

Ouch.....

Sometimes while riding,

feeling the sense that everything about the ride feels great,

I look down at the pavement moving below and think to myself...

This is my choice of vehicle, speed and terrain. I could be down there on the ground in the next second if I something goes wrong.....

riding my 'one wheeled' self balancing vehicle.

I hope your injury heals and sees you back into the cockpit of your profile photo.

?

Link to comment
Share on other sites

Just for my own education I'm trying to recover the battery manually by charging each set of cells with my Rigol DP832 power supply.  This allows me to regulate both voltage and current to charge using the same profile a LiPo charger would use.  It will be a 1A constant current up to 4.0V (lower than normal on purpose) and then will do constant voltage while decreasing current.  For safety, the battery is in a LiPo bag to contain the worse case fire.  I'm also regularly checking the cells to make sure they aren't getting warm.    If this cell recovers, I'll have to charge or discharge the other cells one by one to 4V in order to balance everything.  

If I recover the pack, I do some discharge testing to see how the cells perform next to each other and will also try installing LiPo alarms on the pack to warn me of any cell that gets too low with loud beeping.

IMG_3432.JPG.4ced4557c95f29c86d0c2f755c4292fe.JPGIMG_3431.JPG.a97efd529a3115c750811377d8317253.JPG

Link to comment
Share on other sites

On 1/3/2018 at 5:46 AM, Cranium said:

Thanks for sharing this.  I'm a bit more concerned now.  lol.  The soreness/tenderness I have is on the outside of the wrist below the pinky so while it wouldn't be the scaphoid I guess it could be one of the other bones in there.  But I'm going to go have it checked out just to be sure there isn't something wrong though.

Sorry to read about your incident. I hope you recover soon.

My ACM did the same as your Ninebot and just cut pivoting me forward so, as you said, there's no time to react. I fractured my right elbow, which still won't straighten and hurts if I carry too much & too long. I also chipped a bone in my wrist, which also still gives me aches/pain. I think most of the pain I had in my wrist was around the same area as yours. Initially it wasn't x-rayed as the focus was on my elbow and visible face/eye injury but when I went back to have a follow up on my elbow as it was still hurting quite a lot they decided to x-ray the wrist. That's when they found the chip but said there was nothing they could do.
 

  • Upvote 1
Link to comment
Share on other sites

3 hours ago, Cranium said:

f this cell recovers, I'll have to charge or discharge the other cells one by one to 4V in order to balance everything. 

please forget the defect, low cells! From my knowledge of using about 200 of those 18650 cells for vaping:

Once they got into this state and loose their power, they will never ever recover properly again. Yes, you might bring them to live again. 

But for sure, as soon as they have to deliver some more amps, they sag down again massively and you might faceplant again!

Also: From the numbers you posted not only cell block 5 is defect, also cell block 1 is to far away from the other cells and shortly before going to die i would suspect...

Edited by KingSong69
  • Like 1
  • Upvote 1
Link to comment
Share on other sites

7 hours ago, KingSong69 said:

Also: From the numbers you posted not only cell block 5 is defect, also cell block 1 is to far away from the other cells and shortly before going to die i would suspect...

I agree.  They've gone, don't wast time trying to revive them.  You'll never Feel at ease riding that pack again.  If you can afford that fancy gizmo charger, you can spring for replacing those three cells, YES THREE. cell 4 is crap too.  Makes the decision easier really.  Now you really have a good reason to get stuck in and dig out all that rot.

and possibly cell 9 too.

Edited by Smoother
Link to comment
Share on other sites

12 minutes ago, Smoother said:

I agree.  They've gone, don't waste time trying to revive them.  You'll never feel at ease riding that pack again, unless you purge ALL the rot  If you can afford that fancy gizmo charger, you can spring for replacing those three cells, YES THREE. cell 4 is crap too.  Makes the decision easier really.  Now you really have a good reason to get stuck in and dig out all that rot.

and possibly cell 9 too.

 

Link to comment
Share on other sites

11 hours ago, KingSong69 said:

please forget the defect, low cells! From my knowledge of using about 200 of those 18650 cells for vaping:

Once they got into this state and loose their power, they will never ever recover properly again. Yes, you might bring them to live again. 

But for sure, as soon as they have to deliver some more amps, they sag down again massively and you might faceplant again!

Also: From the numbers you posted not only cell block 5 is defect, also cell block 1 is to far away from the other cells and shortly before going to die i would suspect...

I agree that I won't trust this pack.  But it would be a good pack to do some experiments on.  And with that said, I'm questioning if any of the batteries are actually damaged rather than the pack just becoming severely unbalanced.  This is what I intend to find out.

The batteries in this pack are LG HG2.  The spec sheet can be found here: https://cdn.shopify.com/s/files/1/0674/3651/files/lg-hg2-spec-sheet.pdf?18079372476502823776

The BMS cuts off the output of the pack if a cell gets down to 2.8V.  The rated low voltage of these cells is 2.5V which, as far as I can tell, was never reached.  So no cells appear to be over-discharged.  But testing will determine if this is indeed the case.  And this allows me to test installing LiPo alarms along with balancing leads so it can be balanced using one of my RC LiPo chargers.  My LiPo chargers can also test battery impedance; however, this won't be completely reliable since there are two cells in parallel.  But it would at least provide an indication of an issue internal to the battery if the impedance of one cell is much higher than the others.  

  • Like 1
  • Upvote 1
Link to comment
Share on other sites

51 minutes ago, Cranium said:

to do some experiments on.  And with that said, I'm questioning if any of the batteries are actually damaged rather than the pack just becoming severely unbalanced.  This is what I intend to find

Nope, the numbers you have showed are not possible without the cells beeing defect.

In a serial configuration the cells all natural get on the same level (thats why some producers let go of the balancing charge feature, because they balance anyway). If they are not, like in yourcase, some of the cells are defect.

In a serial pack there might be a difference of maximum 0,1 Volt per cell, because of some quality differences, anything higher shows a cell defect. The cells MUST balance...if they can not/do not they are defect. Sorry...my language barrier, can not explain better :-) 

As long as the cells are connected serial...they balance ALL the time, a difference like 2,8 to 4 Volt might even lead to a venting/blowing of the pack.

 

And to some of the numbers: These 18650 have a "technical" max limit of 2,5 Volt,yip,  thats right!

But: Normally you call a 18650 empty and stop discharging it at 3,3 Volt! (max 3,0 Volt) When our EUC is at 0%, the cell voltage should be at about 3,3Volt per cell. That goes for all EUC i know.

  • Upvote 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...