INMOTION V11 (2020)

[Unventor]

5 hours ago, Wise Rides said:

I've been thinking about building an expansion batter pack for the V11, but I'm not a battery guru so I'm still in the research phase.  Wanted to see if anyone knows how the V11 battery pack is currently wired (how many cells in series and how many cells in parallel, and what BMS is used). 

It's my understanding that the V11 uses LG or Samsung ING 18650's cells.  Samsung's version is 3.6v with 3000mah with 10A continuous, 20A bursts.  LG's are 3.7v, 2500mah with 20A continuous.  Thus, there must be at least 22 - 24 cells wired in series (increases voltage) and at least two battery packs wired in parallel to increase the amperage over 20A (2200 watt motor = A x 84V battery; A = 26 (max amperage draw)).  

Am I looking at this correctly?  Wouldn't I need a similar size battery size/configuration as an upgrade so I'm putting the same volts and amps into the motherboard?  I suppose I would need the cells wired into a BMS which is then wired into the motherboard.  Hopefully, the motherboard would function as normal with the extra battery pack since its putting out the same voltage and amperage as the integrated battery.  

If I can pull this off I'm redesignating my wheel as the V11ER (extended range)!

Nope. Just don't do it. 

What you call research is not going to get you to the level of knowledge to make a safe battery pack. This is not 2 pieces of plywood you just glue together. There are REAL danger involved if you don't know what you are doing. 

There are businesses that make special battery packs. But it needs to communicate with the rest of the electronics and firmware of the V11. 

There is no cheap way around this. Please take the advice of @RagingGrandpa and @mrelwood. Battery packs at these sizes are very dangerous if not handled right. When people give advice here it is giving so nobody harm themselves because they didn't know what they are getting into. It has nothing to do with parenthood. 

[goatman]

i made a backpack battery with a 3d printed magnetic break away connector with the pos and neg magnets reverse pole so it cant be connected reverse polarity.

if  the wheel takes off it cant be tethered to you by the backpack battery leads plugged into the charging ports. thats all ill say about that

[RagingGrandpa]

11 hours ago, goatman said:

i made a backpack battery

Wrong thread?

(What does that have to do with V11? V11 can't charge-and-ride...)

[goatman]

why not?

edit, i went and watched a teardown video, why on earth do they build wheels like this?

Edited January 21, 2022 by goatman
add text

[Wise Rides]

On 1/19/2022 at 10:34 PM, goatman said:

i made a backpack battery with a 3d printed magnetic break away connector with the pos and neg magnets reverse pole so it cant be connected reverse polarity.

if  the wheel takes off it cant be tethered to you by the backpack battery leads plugged into the charging ports. thats all ill say about that

Would love to see more about your battery.  I like the idea of "break away" system.  I had thought about making a second battery pack a permanent part of the wheel but the flexibility of removal makes a lot of sense.

Despite the trepidation on this forum about building batteries, it's common in the e-bike world to build a custom pack.  It's really not that hard.  However, when integrating a new battery with an existing system, you need to make sure it operates as one battery under load (and when charging).  This requires either expanding the existing battery pack or integrating a separate pack into the system.  If you integrate a separate pack then it should be capable of the same level of performance as the existing packs.  That way there's no imbalance or stress on the different packs, they all operate as one.  Of course you'll need to confirm this with the software on the motherboard.  I'm curious to know what the v11 firmware looks at, whether it can automatically detect an increase in battery capacity or not. 

To me, the v11 is a great platform, it just needs a little more range.  If it had the range of a Sherman then it would be unnecessary upgrade the wheel, unless you really want to go faster.  In my case, distance is my goal, not speed.  Cruising at 26-30 mph is just fine for me.  Typically my average is 18 mph anyway (with stops, starts, and slowing down to be courteous to others on the trail/paths). 

[goatman]

24 minutes ago, Wise Rides said:

Would love to see more about your battery.  I like the idea of "break away" system.  I had thought about making a second battery pack a permanent part of the wheel but the flexibility of removal makes a lot of sense.

Despite the trepidation on this forum about building batteries, it's common in the e-bike world to build a custom pack.  It's really not that hard.  However, when integrating a new battery with an existing system, you need to make sure it operates as one battery under load (and when charging).  This requires either expanding the existing battery pack or integrating a separate pack into the system.  If you integrate a separate pack then it should be capable of the same level of performance as the existing packs.  That way there's no imbalance or stress on the different packs, they all operate as one.  Of course you'll need to confirm this with the software on the motherboard.  I'm curious to know what the v11 firmware looks at, whether it can automatically detect an increase in battery capacity or not. 

To me, the v11 is a great platform, it just needs a little more range.  If it had the range of a Sherman then it would be unnecessary upgrade the wheel, unless you really want to go faster.  In my case, distance is my goal, not speed.  Cruising at 26-30 mph is just fine for me.  Typically my average is 18 mph anyway (with stops, starts, and slowing down to be courteous to others on the trail/paths). 

i just soldered the break away to the battery xt60, if you tap into the leads between the battery/bms and controller it shouldnt mess with any communications between the bms and controller. i decided to just scrap the shell and build my own case to carry more batteries (i use magnets to build batteries also) and more powerful controller, its on this forum

https://endless-sphere.com/forums/viewtopic.php?f=35&t=114102#p1688618

Edited January 27, 2022 by goatman

[jmsjms]

I don't know if this question has been answered before: When my V-11 is about to die one day and it shuts off forever, if it happened to be during riding -- would it lock up just like the V-12 has been having issues? I am asking this because my 1-year warranty has expired (or is expiring soon). I thought that it would be a really bad end if one day it just dies during riding and throws me off of it tumbling on the road.

[meepmeepmayer]

14 minutes ago, jmsjms said:

When my V-11 is about to die one day and it shuts off forever, if it happened to be during riding -- would it lock up just like the V-12 has been having issues?

Yes.

There's only one failure mode here, with all electric unicycles. Board dies - you insta crash. (The tire will probably locked by the short then, not sure if this is what you mean.)

But there is no reason to assume your board would suddenly die (at the end of the warranty period or at any other time). Boards tend to die right away from bad components (or unsuited ones, like presumably with the V12's old board) or they tend to live forever. Wheels suddenly dieing mid-ride "for no good reason" is extremely rare.

Unless you have specific reports about V11 boards (or the boards of any other wheel you are riding) dieing mid-ride, there is nothing to worry about.

[jmsjms]

"There is nothing to worry about?" I am worrying because if the crash is at high speed it may be fatal. How much longer should I keep it riding without worrying: a year, two, five years?

Has it happened to anyone with a V-11? I think the oldest V-11s are about 1.5 years old, aren't they?

Couldn't the manufacturers figure out a way that when the board dies, it will disengage the wheel to neutral -- just like a car does when it brakes down -- and will not lock the wheel?

Are there wheels that switch to neutral when the boards die? Maybe I'll consider that to be my next one.

Edited January 27, 2022 by jmsjms

[Paul A]

Many youtube videos show riders cutting out at the maximum speed.

Some have little injuries, others can break clavicles/bones, etc, even with protective gear on.

A terrible scenario would be to hit or be run over by a car/bus/truck in the event of a cut out.....there have been fatalities with regards to other vehicles.

If it were possible for the electric motor of an EUC to free spin, the rider would fall over anyway.

 

[meepmeepmayer]

@jmsjms

For the (very tiny) chance that a sudden cut-out happens, you wear a (full face) helmet. This is just how it is with all electric unicycles. They are instable and actively balanced by electronics, so if the electronics fail for any reason, there can only be one result.

If the tire locking up bothers you, I don't think that makes a difference to it being in "neutral". You still wouldn't keep rolling, you'd just fall the same. Note how the tire has a certain resistance when the wheel is off (due to the magnets causing back-EMF as soon as they are moved). That never goes away. And even if it did and you had a fully "neutral" freely rotating tire, you would still fall (but maybe on your back if you were braking at the time) like on super slippery ice. If you have the idea you could somehow keep rolling without active balancing, that wouldn't work.

(The tire usually locking is due to the entire motor being shorted by an electronics failure connecting some things that shouldn't be connected. Not only is there the question which hardware design could prevent locking, as said above it would make no difference and introduce more potential points of failure, so nobody bothers with it.)

Again, your V11 board does not get more likely to fail just because it is older and more used. If i worked till now, this is a sign of its quality. It's going to keep working.

People would not be riding EUCs if sudden hardware failure crashes were anything but a one-in-a-zillion freak occurrence. It's a tiny tiny tiny chance you take, and maybe a mental hurdle one needs to overcome that this (theoretical) possibility exists. Be aware, wear a helmet, then forget about it and enjoy the ride The real danger is you making errors or some car hitting you etc.

The one exception is known bad hardware, usually with known specific causes like misplaced hot glue (Nikola 84V first batch) or bad components (original V12 board that apparently isn't good enough). They get fixed fast, because nobody likes a wheel model or manufacturer that has any real chance of hardware failure crashes.

And all others are as safe as an electric unicycle can be. I'm not aware of any V11 board issues. Even the old wheels with laughable weak board components (in comparison to today) don't show any signs of suddenly dieing after a certain time or mileage. They just keep working.

Side note: Most (meaning virtually all) crashes you see are overleans, where people overpower their unicycles (usually) at top speed. These are not hardware failure cut-outs. Maybe it helps to be aware of this.

Edited January 27, 2022 by meepmeepmayer

[Tawpie]

1 hour ago, jmsjms said:

Has it happened to anyone with a V-11?

Yes. And the instance I know of personally the rider was wearing all their gear and was unhurt other than a few scrapes and bruises. It was a hardware failure, cracked MOSFET, these things do happen.

There is a finite and real chance that something will break on your wheel, and there is a greater chance that you or something else will make a mistake and an accident will be the result. You can get hurt badly, even killed... this activity has real risk. Like owning a gun, or riding a motor bike, or a bike bike, or walking on ice, or driving a car.

Do what you can to reduce your risk to a level that is acceptable to you—that may mean finding another hobby, it may mean wearing 25 lbs of protective equipment like I do, it may mean never going very fast (me) or on uneven ground (not me), it may mean not buying an IM wheel (that eevee's called out as their worst manufacturer for reliability).

But by all means, if you're not comfortable with the risk, don't take it. This is fun, but the risk involved is definitely not for everyone.

Edited January 27, 2022 by Tawpie

[Paul A]

What are the rankings for manufacturer reliability?

Or is it more accurate to list reliability rankings for EUC models...

[Tawpie]

7 minutes ago, Paul A said:

What are the rankings for manufacturer reliability?

It's the unverified opinion of a single distributor, but checkout Eevee's 2021 end of year awards (cheesy yeah, I didn't particularly enjoy it). They nominated LeaperKim, Begode, and KS for most reliable and gave the award to LeaperKim even though they clearly state that they've never had a single warranty claim on their Begode sales. IM was not nominated and they rant on a bit about how IM needs to up their game.

Edited January 27, 2022 by Tawpie

[AtlasP]

10 minutes ago, Tawpie said:

It's the unverified opinion of a single distributor, but checkout Eevee's 2021 end of year awards (cheesy yeah, I didn't particularly enjoy it). They nominated LeaperKim, Begode, and KS for most reliable and gave the award to LeaperKim even though they clearly state that they've never had a single warranty claim on their Begode sales. IM was not nominated and they rant on a bit about how IM needs to up their game.

Leaving aside the current situation with the V12 as I've not been able to keep as close an eye on it as I normally do (busy few months IRL), in talking with distributors I had historically heard that IM has more OOTB (out-of-the-box) failures and/or failures where the wheel just won't turn on one day for seemingly no reason, but less failures while ridden compared to other brands. So you're more likely that an IM wheel might be DOA (dead on arrival) or else dead on wakeup so-to-speak, but then if it starts/works fine you're less likely for it to fail while riding/at speed compared to other brands. I don't know whether that remains true with the V11 and/or V12 in the mix. If true, it makes sense that this would be more annoying/less desirable for distributors (total warranty claims to deal with) but ultimately that sounds more desirable/superior for me as a rider.

Edited January 27, 2022 by AtlasP

[meepmeepmayer]

If I had to guess, I would say the variance between individual boards of a specific model might very well be similar (or even greater?) than the variance between different models, let alone manufacturers. Going by the fact that most board failures, if they happen, seem to happen right away (and should just have been caught by quality control).

So I'm not sure comparing failure rates is meaningful, when all kinds of models and failure modes are thrown into one number.

As far as "dies mid-ride after some time when you thought everything was good" rates, they are tiny for all manufacturers. That's the important bit

I would say the V11 is in that good group. All wheels are, specific issues excluded.

[Funky]

Would it not be possible to make second board? Both work same time, but if one fails.. The second one keeps euc running? If one dies, it would show by flashing lights or somehow? (Generally for any euc..)

Is it even doable? 

 

Edited January 27, 2022 by Funky

[Tawpie]

6 minutes ago, Funky said:

Would it not be possible to make second board? Both work same time, but if one fails

100% possible. Also 100% unlikely. Too costly... besides, you'd want three so that they could all vote and majority rules. And even then, it only mitigates a specific set of risks. NASA used triple redundancy and still had Apollo 13 (which to be fair was not due to a hardware failure so their hardware redundancy was moot, it was due to not fully understanding what happens to cryogenic liquids in zero gravity—but even though their hardware failure risk was very small, they still had an event that almost killed the crew).

 

Edited January 27, 2022 by Tawpie

[Paul A]

Gotways/Begodes spontaneously combusting would be unreliability.....

[Paul A]

A parallel second board for redundancy is actually possible?

Sounds like a worthwhile cost, one part of protective gear.

[Funky]

1 minute ago, Tawpie said:

100% possible. Also 100% unlikely. Too costly... besides, you'd want three so that they could all vote and majority rules.

Yeah, i don't see any euc builder doing that.. But if it's possible. It would be so much safer no?

Cost is Cost.. For safety of second board.. (Knowing that wheel won't die suddenly 100%) I would pay 2x price of regular euc.. Piece of mind is worth that.

[Chriull]

8 minutes ago, Funky said:

Would it not be possible to make second board? Both work same time, but if one fails.. The second one keep euc running? If one dies it would show by flashing lights or somehow? (Generally for any euc..)

Is it even doable? 

Hardly, as the mosfets normal failure mode is short circuiting. So one would have to disconnect the malfunctioning board with something else than mosfets, as they could short circuit too in case of malfunction.

6 minutes ago, Tawpie said:

100% possible. Also 100% unlikely. Too costly... besides, you'd want three so that they could all vote and majority rules.

So it's not some algorithmic/random failure which 2 of three could decide, it's permanent failure of a board caused by "thermal design insuffciencies"==mosfet overburdening.

 

Edited January 27, 2022 by Chriull

[Paradox]

Just now, Paul A said:

Sounds like a worthwhile cost, one part of protective gear.

A spare tire could help in certain situations! 🤣

[Paul A]

https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20220127142554&SearchText=inmotion+v11+controller

Aliexpress, V11 controller, about $47 USD.

[Chriull]

2 minutes ago, Paul A said:

Aliexpress, V11 controller, about $47 USD.

€ 284,53 | Original Inmotion V11 Controller Mutter Board Haupt Board V11 Fahrer Bord V11 Bluetooth Board Teil für Inmotion V11 E-rad
https://a.aliexpress.com/_msXNn1q

... That's the one normally to replace after malfunction...