Poll: Have you experienced an unexpected shut-off while riding?

[Jug]

21 minutes ago, nute said:

Didn't hurt myself, few cuts on fingers but was wearing wrist guards so they took the worst of it.

That is good to hear, but anyway it is strange that it shut off with 80% capacity 340w battery, there is a lot of juice and lot of "space" for regenerative braking,

and on another side you managed to go up steep but down steep failed! Strange   

[nute]

I think i over leaned, panicked a bit as the down was steeper than i thought and leaned way back. Poor wheel has taken quite a few knocks today

On the plus side part of my route was over a busy main street, past a policeman, who just watched and didn't say anything. I was going very slow and being very careful to avoid people.

[tjcooper]

New problem with the MoHoo:

I have been using the MoHoo only to learn better how to "hop up" and not use training wheels.  Seems to work fine for the first 10-20 minutes.  Then I have several things starting to happen.  If I am going forward (4-6 mph) I have the abrupt stop (face plant)  that I have detailed and put the pictures on YouTube for everyone.  But when I am doing the static "hop up" tests, I am now seeing the MoHoo just dropping out of gyro balance when I put a load on it (like jumping up and trying to stop from going forward or backward).  Tonight I had something new happen.  After 10 minutes to "hoping up" and tried to use my other foot and the EUC just stopped balancing on every attempt.  SO I tried with my hand on the handle to just push down on petals (virtually) and give it significant force in the push.  After a couple of "pushes" the gyro just stopped balancing and the wheel just rolled like a bicycle.  Reset the button and start over and the same things happens many times.  I was only making the petals move like 1-2 degree of downward slant to emulated the lean of going forward.   I had seen this in the past when I was riding for 20 minutes and assumed it was me just loosing my balance.  But in this test my hands had "perfect balance" as I rolled the wheel forward and back.   It only took a few degrees of tilt forward or backward and the shut down happened.  Needless to say I stopped practicing because that is a great way to do Nute's "arss plant".

The clincher was that after I had recharged the system (only 41 watts put into battery) that my "hand roll" could not cause the failure to happen again.   I think this really points to a failure in the battery system.   I wish Banggood would give me permission to tear apart the battery and put leads on all cells to see if I have a "weak sister" in the 16 cells.   I would then put it under strong resistive load and see if any of the cells buckled under the current load.   Banggood is really pushing me to accept the IPS I130 as my replacement.  I really want the Ninebot E+ where I pay the difference, but they say they cannot ship that unit to the USA any more.  I have even offered to have them ship it to USA without a battery and I would buy one over here and install.  Still waiting to see what will be the outcome.

BATTERY SPOT WELDING:  I have done spot welding on NiMd batteries for years for my RC airplanes.  We used to believe that only spot weld was good enough for the 100-500 amp systems we flew.  But later we all found that wire mesh strips with solder could do everything we needed and not require special equipment for assembly.  There are "hammerhead" soldering irons that will heat both the positive and negative ends of two batteries simultaneously and allow them to be fast pushed onto the wire mesh and get great connectivity.

Early on we all experimented with spot welding.  Dumb as it seems, we just charged up a 10,000 microfarad capacity to 12 volts DC and just shorted that to our "two nail" assembly on the battery tip (or base).  By just adjusting the size of the capacitor and the voltage applied, we could get perfect welds each time.  We wasted a few NiMd dead cells finding out what was the proper capacity, but once that experiment was done, we could get repeatable welds every time.......we did waste a few nails trying to get the proper spacing on the tin strips.  FYI.

     tjcooper

[Shoe73]

@tjcooper The IPS should give you a better experience than MoHoo, should you accept it. I have two IPS EUCs and I've been completely satisfied with them. 

[Jdestef]

1000+ miles on a NBO E+ v1.2.2 with no shutoffs here.

 

[thaikiwi]

Did ~400km since Feb. this Year and no shutoff so far on a NB1E+v1.3.5.

[Jug]

On 5/1/2016 at 1:14 PM, Reivax said:

Amazing ! Please let us know the outcome !

So to not hijack anymore this thread, i have update of finishing spot welder and battery pack on this thread , enjoy!   

[tjcooper]

Shoe73,

can you tell me what models of IPS you have?

   tjcooper

[Shoe73]

On May 18, 2016 at 11:16 PM, tjcooper said:

Shoe73,

can you tell me what models of IPS you have?

   tjcooper

 Have the 12" A130 that I got for my son but I ride it too (very light and surprisingly speedy) and the 16" Xima Lhotz (powerful and fast).

As a side note: One thing about IPS is that they integrate the battery management system into their motherboard, running wires for each battery cell to the board, so they are actually monitoring all the battery cells individually. I think this has led to their good safety record. 

[dubgee2002]

Sorry, not sure if the right place to put this.

My TG-T3 shuts off at a really slow speed, equivalent speed to a person with a brisk walk.  Battery is full so its not that, and its not a lean/speed issue since its really slow. Really hesitant to ride now. Any suggestions on how to fix? or is it dead? 

[Hunka Hunka Burning Love]

How old is it?  Did you check the tire pressure?  If there is a problem with a battery cell(s) in the pack it might appear to be fully charged, but it could be providing less voltage than it normally should.  Are you able to check the voltage at the XT60 connector if you have a voltmeter / electronics experience?  One other possibility is a bad charger.  The ones they ship with the cheaper wheels are pretty cheaply made.  Can you check the output voltage on the charger?

[dubgee2002]

EU is about a year old? Tire pressure is ok. Charger has been fine...until this happened. From the recommendation of this forum, i've charged it after every use, even if its only been like 10 min of ride time. 

don't have a voltmeter. maybe I have to look into one? 

[tjcooper]

UPDATE on MoHoo:

I finally got Banggood to say that the MoHoo was beyond repair and they would refund my money.  I keep checking PayPal but I think it will happen this week.  Found that fantastic deal on forwardCA, and bought the Ninebot E+ "flash" for $449 plus tax.  Shipped and came to me in ONE DAY......unbelievable good service.

my son came from graduate school this weekend and wanted to ride both MoHoo and NB.  He is good athlete and could ride "sort of" in just a few minutes.  We had the same problem with MoHoo.   In about 10-15 minutes of riding around, the system would stop running the gyro when you jumped on.  And he weighs much less than me...around 150lbs.  So I think that nails the proof that the MoHoo at least has a bad battery.   He and I both tried out the NB E+ and it was like night and day.  No problems hopping up and going forward.  We did this on the grass because we didn't have the safety foam fully on unit yet.  But you can ride over the bumps in the grass with no drop outs or power down.   Only wish as a starter I had known about the huge safety differences in machines before I made my first purchase.

Maybe California will require a new label on all EUC's:  "face plants will come to all riders over 80KG who have batteries less than 320 Wh or motors less than 500 Watts".  There is alot of truth in that statement.   I just hope that Banggood comes through on their promise and I get my original purchase back.

    tjcooper

[SlowMo]

35 minutes ago, tjcooper said:

I just hope that Banggood comes through on their promise and I get my original purchase back.

Won't they require you to send back the faulty unit for refund?

[steve454]

On 5/11/2016 at 1:57 AM, tjcooper said:

New problem with the MoHoo:

I have been using the MoHoo only to learn better how to "hop up" and not use training wheels.  Seems to work fine for the first 10-20 minutes.  Then I have several things starting to happen.  If I am going forward (4-6 mph) I have the abrupt stop (face plant)  that I have detailed and put the pictures on YouTube for everyone.  But when I am doing the static "hop up" tests, I am now seeing the MoHoo just dropping out of gyro balance when I put a load on it (like jumping up and trying to stop from going forward or backward).  Tonight I had something new happen.  After 10 minutes to "hoping up" and tried to use my other foot and the EUC just stopped balancing on every attempt.  SO I tried with my hand on the handle to just push down on petals (virtually) and give it significant force in the push.  After a couple of "pushes" the gyro just stopped balancing and the wheel just rolled like a bicycle.  Reset the button and start over and the same things happens many times.  I was only making the petals move like 1-2 degree of downward slant to emulated the lean of going forward.   I had seen this in the past when I was riding for 20 minutes and assumed it was me just loosing my balance.  But in this test my hands had "perfect balance" as I rolled the wheel forward and back.   It only took a few degrees of tilt forward or backward and the shut down happened.  Needless to say I stopped practicing because that is a great way to do Nute's "arss plant".

The clincher was that after I had recharged the system (only 41 watts put into battery) that my "hand roll" could not cause the failure to happen again.   I think this really points to a failure in the battery system.   I wish Banggood would give me permission to tear apart the battery and put leads on all cells to see if I have a "weak sister" in the 16 cells.   I would then put it under strong resistive load and see if any of the cells buckled under the current load.   Banggood is really pushing me to accept the IPS I130 as my replacement.  I really want the Ninebot E+ where I pay the difference, but they say they cannot ship that unit to the USA any more.  I have even offered to have them ship it to USA without a battery and I would buy one over here and install.  Still waiting to see what will be the outcome.

BATTERY SPOT WELDING:  I have done spot welding on NiMd batteries for years for my RC airplanes.  We used to believe that only spot weld was good enough for the 100-500 amp systems we flew.  But later we all found that wire mesh strips with solder could do everything we needed and not require special equipment for assembly.  There are "hammerhead" soldering irons that will heat both the positive and negative ends of two batteries simultaneously and allow them to be fast pushed onto the wire mesh and get great connectivity.

Early on we all experimented with spot welding.  Dumb as it seems, we just charged up a 10,000 microfarad capacity to 12 volts DC and just shorted that to our "two nail" assembly on the battery tip (or base).  By just adjusting the size of the capacitor and the voltage applied, we could get perfect welds each time.  We wasted a few NiMd dead cells finding out what was the proper capacity, but once that experiment was done, we could get repeatable welds every time.......we did waste a few nails trying to get the proper spacing on the tin strips.  FYI.

     tjcooper

Stop riding that thing, something is wrong with it.  You may have gotten a bad one.  

[Rehab1]

An unexpected shut down sounds ominous and by the sounds of it  there is no way to practice for this unfortunate event! When I flew helicopters we would cut the engine all of the time and practice auto rotations both in a hover and at 1000 feet.  It became second nature to go through the controlled maneuvers in the event you had an engine failure. This situation on the other hand relies totally on luck. Kind of hard to file a lawsuit against the Chinese after you are all busted up.

[Shoe73]

9 hours ago, Rehab1 said:

An unexpected shut down sounds ominous and by the sounds of it  there is no way to practice for this unfortunate event! When I flew helicopters we would cut the engine all of the time and practice auto rotations both in a hover and at 1000 feet.  It became second nature to go through the controlled maneuvers in the event you had an engine failure. This situation on the other hand relies totally on luck. Kind of hard to file a lawsuit against the Chinese after you are all busted up.

I was thinking of practicing in the grass at the park, taking a short stick to press the power button, and trying to run off the wheel at different speeds, just to see what it feels like.

[Ricardo Gomes Barbosa]

I just had an unexpected shutdown on my Ninebot One E+. The battery was under 40%, as I leaned to speed up I expected a tiltback, however, for my complete shock the pedals bowed down forward not giving me any chance of reaction. The result was a violent fall, as a consequence I had injuries on both hands, knees and right shoulder, and a moderate blow on the right cheek and ruined my favorite jacket. I lost confidence in this device.

[steve454]

I would say, never go below 50 percent.

[tjcooper]

UPDATE:

just wanted to say that Banggood.com came through on their promise and refunded my purchase.  No request to return old unit.  Given that I am a physics person with unstoppable curiosity, I will tear apart the battery of MoHoo and see if any of the cells are "weak".   If that is the case, I will rebuild the battery with new cells and test again.  If that is not the cause, then a new motherboard would be needed.......and not sure that would be a solution for a heavy guy like me.......but it might work for my light weight son.   Will let you know what I find.

Cannot describe the huge difference to the NB E+.   No problem hopping up and riding 10-15 feet.  Just need more practice to get my "wheel on right".  Thanks for all the help and suggestions from this forum.  Would have been a "walk away and never come back" from EUC if your comments had not told me that this was not just my problem.  Thanks.

    tjcooper

[AlanR]

@tjcooper would be interested in your findings. The manufacturers [Chinese] don't want to discuss anything; zero after sale service.

My  first, a generic failed quite a few times - shut-off completely - gave manufacturer all the statistics - they even tried to blame 'the rider' without specifics - I sent them a video and asked to point out exactly where I rode 'incorrectly' - no reply.  It was cheap but for just 7 weeks to failure, costly on a per day basis.

My 9B1E has been good to date.

 

@Ricardo Gomes Barbosa very sorry to hear of your fall on a 9B1E+. Yes, failure is so instantaneous that I believe its virtually impossible to train / prepare for it.

At 40% battery I would have thought you would have had another 20% usable capacity. Many here speak of running at 10% battery!!!  Were you pushing the limits of speed, climbing, in snow etc?  

Hobby Gadget Factory's Fred [@esaj knows where to find this sort of info] sent me shunting circuitry for my generic. Can't be sure I have done [soldering well enough] but also I'm nervous riding without hanging onto a wheelchair!  It has shut-down since the first soldering!

 

[tjcooper]

AlanR,

I took the MoHoo (which I believe is manufactured by Huanix as the H1 Plus) battery apart.  It is a complete BMS with battery as one unit made by Samsung.

All 15 of the 18650 cells have their own FETs and control logic.  All the 15 units have a massive 4 super-FET control structure that feeds the XT-60 connector..

There is a set of 3 parallel diodes and resistor that feed the 15 parallel cells to another connector which is the Deans connector.  It reads 0.8 volts less than the XT-60 connector.  I assume it is some sort of feedback voltage control to the main motherboard.  I had assumed it was just a 3S serial connector to the motherboard to provided 12vDC for the Bluetooth etc.  I was very wrong.

Does anyone have the schematics for the Samsung 15s battery pack (132 Wh unit)?   I want to charge up unit and then put it under resistive load and see if any of the 15 cells might be weak.  Has anyone else performed this test?  I am looking for a "weak sister" cell that looses its voltage much quicker than the other cells.  This would explain why the unit does "abrupt stop" after 10-15 minutes of very moderate use.   Any ideas of whether I would look to get schematics for this type of battery pack?   Much thanks.   I am working directly with Huanix and will let you know how helpful they are in trying to find a solution to the problem.

    tjcooper

[Chriull]

The 0,8v difference should be the voltage inversion protection diode at the charge side.The main schematics of the charge/discharge part should be more or less like shown here:

 

[Rehab1]

@Ricardo Gomes Barbosa That is terrible news! I hope you are OK. Sounds like you suffered some injuries. Bummer!  I have never experience a power off on my NB1 E+ while riding but there has been many discussions on this forum on trying to prepare for such an episode. Hopefully you can find the answer on what caused the shut off. There are many skilled individuals on this forum that will probably be contacting you for more information. Unfortunately my lack of expertise will be of no assistance. Sorry you have lost confidence. Hopefully you will find some answers and once again feel secure riding your NB1!  Be well!

[steve454]

On 6/11/2016 at 0:08 PM, Ricardo Gomes Barbosa said:

I just had an unexpected shutdown on my Ninebot One E+. The battery was under 40%, as I leaned to speed up I expected a tiltback, however, for my complete shock the pedals bowed down forward not giving me any chance of reaction. The result was a violent fall, as a consequence I had injuries on both hands, knees and right shoulder, and a moderate blow on the right cheek and ruined my favorite jacket. I lost confidence in this device.

Oh no!  How much did you lean to speed up?  That is one of my bigger worries, that I will overlean the machine.  I have gotten some good acceleration from the NB1 E+ for short distances but am afraid to really push it.  I have overpowered a couple of generics and they just did not have the power to keep my weight upright when leaning too far forward, so I am cautious on the Ninebot.  It seems there is a sweet spot where you can speed up quickly without demanding a lot of torque.