The end of BionX?

[LockH]

The plot thickens...

BionX Canada sells off parts of its business:
https://www.bicycleretailer.com/ind...-canada-sells-parts-its-business#.WyxsVWMna1g

Starts:

AURORA, Ontario (BRAIN) — Three companies have purchased parts of BionX Canada following a three-month search for a buyer. According to court documents, Crescent Commercial, Amego Electric Vehicles and NumberCo purchased some of BionX Canada’s assets, including some tooling, machinery, inventory and other equipment. The sales were approved mid-June.

According to court documents, Amego Electric Vehicles purchased 81 complete BionX kits. NumberCo purchased a parcel of motors, batteries and other parts, and Crescent Commercial, which is an auction house and liquidator, bought assembly line and machine shop equipment and other manufacturing tools. Other miscellaneous parts, inventory, hardware, accessories and components remain and are still up for sale, as are BionX’s patents, trademarks, domains and subsidiary shares.

"Amego Electric Vehicles"? Seen here:
https://www.amegoev.com/

GO Virginia! (V. Block, Amego owner, local to me...)

 

[Syonyk]

...and Crescent Commercial, which is an auction house and liquidator, bought assembly line and machine shop equipment and other manufacturing tools...

In case there was any question that BionX was done... you don't part out the assembly line stuff when you plan to go back into business.

They're toast. Sucks for everyone who bought a 48V system. Those will be so much scrap inside 5 years.

 

[LockH]

^^ Hehe... In 2015 you wrote "I've just finished some teardown pictures from a repair of one - the triac blew up (110v version)"... Your first post to the `Sphere. You Techo-Weenie You.. :lol: The BionX hubs just a step along the way to World Domination (for personal use as "vehicles" used in "urban" travels. :lol: LOVE TORQUE! (In a "stop-and-go" urban 21st-Century.) :wink:

 

[Syonyk]

Hm? My first rebuild was the iZip Ultra. I've done plenty of LiMn BionX repair since then, but they have a solid BMS (with the exception of the 11S units - those seem to kill BMS boards). The 48V units are something totally different, and are unreliable as hell. The BMS blows up and then drains the cells because it can't shut down the output transistors.

 

[LockH]

^^ Oh Oh... "unreliable as hell"... NOT "good". [Sigh]

 

[miro13car]

nobody brought it up
but where is government in all this?
federal, provincial?
so much for crowing about protecting Canadian industries.

 

[Cephalotus]

As fas as I understand BionX GmbH in Germany is noe buying the BionX batteries directly from the Chinese supplier.

We will see if new BionX batteries will ba available in the German market. So far they are sold out, so new batteries must come from "somewhere".

Price of 48V 11,6Ah BionX batteries with 13s4p Panasonic PF celss was 600 Euro (incl 19% VAT). That's not super cheap, but compareable to other OEM batteries.

Afaik the 2011 48V BMS have been pure shit, but later ones are quite okay. I have some BionX 48V battreies from 2013 that are perfectly fine today. I don't like their 48V batteries, because the baalncer is shit, imho. Bette to have noe balancer at all.

With battery software 111 and battery hardware 6.2 or lower you it is said that you can run them without the balancer. Just remove the wires #2 to #13 (you should know what you do!)

Supply of BionX motors could be a more significant problem though. There are plenty of PL and SL motors on the used market for cheap prices (I already built my own stock that will last me for many years), but the d-series are rare to obtain.

For new ones you pay 630 Euro (incl VAT), but without rum.

RC3 and DS3 could be in shirt supply, too. difficult to tell. G2 are easily available on the used market. I have built my own stock, too. They usually don't fail, as long as you don't drop them on concrete.

This is one of my new BionX projects:

Street legal (insurance plate below rear light) 45km/h speed pedelec with BionX d-Motor and 550Wh battery that runs very efficient and weights just 19kg. (with some tuning potential left).

with the smaller battery (have to rebuilt it to a 48V system using 13s2p LG HG2 batteries yet) a 17kg speed pedelec will become possible. Inkl fenders, Supernova M99 light, rear rack, mirror and insurance plate.

It's the best bike I have built so far and I have built many. I'm buildig a 2nd one for my girlfriend with a smaller frame and thicker tires.

The d-series runs 53km/h in that bike but for legal reasons I reduced that to 45km/h.

I plan to use my BionX bikes for MANY years to come.

It's the easiest way to use motors with 48V 30A controllers as legal 250W systems in the EU.

(edit: originally both bikes had 11s 40,7V batteries from 2010 without single cell voltage monitoring. Those old 11s battery boards have been perfectly fine)

 

[Syonyk]

(edit: originally both bikes had 11s 40,7V batteries from 2010 without single cell voltage monitoring. Those old 11s battery boards have been perfectly fine)

The spinel LiMn cells ("Konion") will balance properly without a balancer. That is not true of other, more modern lithium chemistries, and you can't get away with the same style pack design on newer cells safely.

 

[Cephalotus]

The spinel LiMn cells ("Konion") will balance properly without a balancer. That is not true of other, more modern lithium chemistries, and you can't get away with the same style pack design on newer cells safely.

"Self balancing" Li-ion batteries do not exist and never have. This is a internet myth like it is a internet myth the li-ion cells have a shelf life of only very few years. Self balancing of Li-Ion cells in series is chemically and physically impossible, no matter the cathode material.

What does exist is cells with very similar self discharge. All of todays quality 18650 cells have a self discharge very near to zero, so all of todays 18650 cells do not drift. Tolarances in self discharge is the only reason for voltage drifting.
A voltage difference at low SOC during dischrage is possible with variation in cell capacity, which can happen or devolp (i.e. if you have hot spots in your cell package), a BMS can shut down that battery and avoid deep discharge of single cell banks, but no balancing will do any good in such a situation.

A BMS with single cell voltage control is a good idea, especially if you want to discharge cells down to 3,0V or even lower, but balancing is replacing high quality cells with cheap electronics. Most professional equipment (military, NASA, vehicles, etc...) does have a BMS with single cell voltage monitoring but no balancer.

The old BionX BMS discharge only down to 3.3V/cell which is a problem for modern high capacity cells, because you only use a part of their rated capacity.

I though about using BionX 11s BMS with 12 cellpacks, but currently I only use 13s cell packs, so I didn't make any tests yet...

 

[Syonyk]

The Konion thread has an awful lot of observations about how this particular chemistry self balances, so check over there for details. I can say that the BionX packs with the LiMn cells, after years of service, have cell groups within 0.01V of each other, so whatever they were doing, works. Spinel LiMn is a weird corner case of lithium chemistry, though.

 

[madin88]

The spinel LiMn cells ("Konion") will balance properly without a balancer. That is not true of other, more modern lithium chemistries, and you can't get away with the same style pack design on newer cells safely.

+1

 

[Cephalotus]

The Konion thread has an awful lot of observations about how this particular chemistry self balances, so check over there for details. I can say that the BionX packs with the LiMn cells, after years of service, have cell groups within 0.01V of each other, so whatever they were doing, works. Spinel LiMn is a weird corner case of lithium chemistry, though.

The internet is full of nonsense and stupid battery myths. I do not need to read something about "Konion" (which btw. is just a marketing name from Kontronik. They also started that nonsese about "self balancing") They Sony LMO cells just happend to be one of the first commercial cells available to a wide public with very low and consistent self discharge rates. They also tolerate abuse like deep discharge quite well, at least the earlier types.

Drifting in a series connection of Li-Ion cells is the result of a variation in self discharge, nothing else.

Self balancing does not exist. Put an empty and a full LMO cell in series and watch... Noting will happen. Can't be easier.

I have Panasonic PF cells and Sanyo UR18650E cells that are perfectly in balance since many years. No drift. Zero. Identical self discharge (near zero) is all it takes.

But this thread is about BionX and imho the 48V BionX batteries would have done much better without a balancer, which causes much more harm than it does any good.

 

[madin88]

Drifting in a series connection of Li-Ion cells is the result of a variation in self discharge, nothing else.

Self balancing does not exist. Put an empty and a full LMO cell in series and watch... Noting will happen. Can't be easier.

I am with you that "self balancing" does not exist.
Whats so good about the that Sony cells (at least the V3 which has been used in the BionX packs without balacing) is the overall quality which is much more consistent / superiour compared to other brands. It is not only self discharge that matters, its also internal resistance, similar capacity etc.
The V3 cells i worked with always arrived with absolutely similar voltage (+- 1mV), while when working with Samsung or other brands the difference was higher in the range of +-3 - 5mV (cells from same batch). And when working with Samsung cells from different batches it was
much higher so i try to avoid mixing batches, while with Sony that was never a problem.

The discharge cut off of 3,3V also helps alot to keep the pack balanced well!

But this thread is about BionX and imho the 48V BionX batteries would have done much better without a balancer, which causes much more harm than it does any good.

Sadly but true.
Instead of balancing and single cell monitoring, measuring the voltage in the middle of the pack (like 5s + 5s) would already make it many times more safe. Makita does this on the 14,4V Power tool batteries. They measuring 2s+2s and don't have balancing function.

 

[Cephalotus]

I am with you that "self balancing" does not exist.
Whats so good about the that Sony cells (at least the V3 which has been used in the BionX packs without balacing) is the overall quality which is much more consistent / superiour compared to other brands. It is not only self discharge that matters, its also internal resistance, similar capacity etc.

Okay, so we do agree here. Small differences in Ri are not so problematic. This is also one the biggest disadvantage of those LMO cells. When aging their Ri increases significantly. Not so problematic for 250W Pedelecs though, but a 250W labeled BionX consumes up to 1400W from its battery.

The V3 cells i worked with always arrived with absolutely similar voltage (+- 1mV), while when working with Samsung or other brands the difference was higher in the range of +-3 - 5mV (cells from same batch). And when working with Samsung cells from different batches it was
much higher so i try to avoid mixing batches, while with Sony that was never a problem.

I had ca. 200 Panasonic PF that have been within 0.01V. Self discharge was exactly zero (within those 0.01V) for some of those cells that have been sitting in the fridge for 3 years.

Now I bought some LG H2. I expect those to be within 0,01V, too. Imho even a voltage difference of up to 30mV over lifetime is perfectly fine in the voltage range from 3.00V to 4.15V where I am using my cells.

The discharge cut off of 3,3V also helps alot to keep the pack balanced well!

It ususally avoids deep discharging of single cells.

Small differences in capacity (which do exist or can develop) have significant impact on cell voltage if you are near 0% SOC.

This is why I do not advocate against BMS and cell voltage monitoring, I just believe that balancing is a solution looking for a problem. I belive that high uality cells never Need balancing, not a single time in 10 years or 1000 cycles. If the cells start drifting they are useless anayway.
Cheap chinese cells do drift, because they vary in self discharge.

Instead of balancing and single cell monitoring, measuring the voltage in the middle of the pack (like 5s + 5s) would already make it many times more safe. Makita does this on the 14,4V Power tool batteries. They measuring 2s+2s and don't have balancing function.

This is a good compromise. Sadly BionX uses 13 cells in series. 13 is a prime number.

My plan is to build some 13s batteries for BionX, useing their older 13s BMS (Hardware 6.2, Software 111) and cut of the balancer. The old ones seem to work that way just fine. I will add external balancing connectors to check them from time to time.

Another idea is to build 12s batteries with their old 11s BMS from Trek/Diamant, but so far I'm not sure if I can switch their charge Limit voltage from 45.7V to 49.8V. The lower end at around 35-36V would be just fine for modern cells in a 12s configuration.

I have collected some of those 11s BionX BMS from the years 2009-2011 and they all worked just fine. (good thing is that all of those do already have the built in DC-DC converters for bike lights which is programmable from 5V to 12V in 0,5V steps)

 

[Syonyk]

Watch out on the 11S Trek BMS boards. I've seen quite a few of those dead, which I can't say of the 10S boards.

Self balancing does not exist. Put an empty and a full LMO cell in series and watch... Noting will happen. Can't be easier.

Put a LiMn at 4.10V and 4.20V in series, then cycle them a few times, and you'll see them work out the differences and come to an equal voltage over a number of cycles. They're not statically balancing, certainly, but the charge efficiency drops off at high SoC enough to let the lower cells catch up when cycled normally in a pack.

 

[Cephalotus]

Put a LiMn at 4.10V and 4.20V in series, then cycle them a few times, and you'll see them work out the differences and come to an equal voltage over a number of cycles. They're not statically balancing, certainly, but the charge efficiency drops off at high SoC enough to let the lower cells catch up when cycled normally in a pack.

The coulomb efficiency (Ah out vs. Ah in) when charging a li-ion battery is around 99,x%. The difference to 100% efficiency is building the SEI (first cycles) and otherwise irreversible destruction of the cell itself (cycle aging).

There is no way the 4,20V cell can absorb electrons. Every electron either moves a Lithium-ion or otherwise destroys the cell. There are no reversible side reactions for Li-Ion cells like electrolysis of water based electrolytes in cells based on nickel or lead which are able transform current into heat (after recombination of hydrogen and oxigen back to water) and not into chemical reaction.

 

[madin88]

The coulomb efficiency (Ah out vs. Ah in) when charging a li-ion battery is around 99,x%. The difference to 100% efficiency is building the SEI (first cycles) and otherwise irreversible destruction of the cell itself (cycle aging).

I don't think the coulomb efficiency of the electrolyte has much todo with self balancing...

What about the internal resistance? It's known that it depends on the S.O.C.
So regarding mentioned example of Syonyk, if two cells one at 4,1V and the other at 4,2V are put in series and you charge them, the cell with 4,2V probabaly will become warmer as the cell with 4,1V.
This would mean each time the one cell becomes overcharged, a part of the excess energy is turned into HEAT wich means the voltage difference will become less and less each time you charge them.
IMO this makes alot of sense and could be the explaination how self balancing works.

Despite all that the Sony V3 cells used in BionX batteries without BMS have outstanding quality and consistency.
If you buy 50 cells and plan to use them without BMS, it does matter if they have differences in capacity and internal resistance of 2%, or only 0,5%.

 

[Cephalotus]

I don't think the coulomb efficiency of the electrolyte has much todo with self balancing...

100% relevant for drifting, because it is a way to loose electrons in a series connection.

What about the internal resistance? It's known that it depends on the S.O.C.

100% irrelevant. Ri does not kill a single electron. Higher Ri means higher internal voltage loss at a given current and more heat, but doesn't change the mAh witin a cell the slightest bit.

So regarding mentioned example of Syonyk, if two cells one at 4,1V and the other at 4,2V are put in series and you charge them, the cell with 4,2V probabaly will become warmer as the cell with 4,1V.
This would mean each time the one cell becomes overcharged, a part of the excess energy is turned into HEAT wich means the voltage difference will become less and less each time you charge them.

NO!

Cells heat up because P thermal = I² * Ri.

But for changing the state of charge you need a loss of electrons in one of the cells. This is impossible in a series connection, where I is the same in every cell (basic physics), no matter the Ri of each sell.
If I is the same and time is the same (obviously), the charging in I*t (Coulomb) is exactly identical.

The only way for drifting is "killing" electrons. This is possible in nickel and lead based batteries because in those batteries electrons can be used for electrolysis of water based electrolyte and this is the reason why their Coulomb efficiency is way below 100%.
Li-cells do not have such reversible reactions.
Every "killed" electron in a series of Li-Ion cells is a small but irreversible destruction of that cell. (= coulomb efficiency below 100,00%)

There is one exception to this and this is (reversible) self discharge. If you want to have Li-Ion cells without drift you need to buy cells with identical self discharge. A self discharge of (practically) zero is also okay and this is what most modern Li-Ion cells have. This is the reason why there is no drift in modern Li-ion cells, except if you buy the Chinese junk.
And this is why there was huge voltage drifting in a series of NiMh cells, because those had huge and various self discharge rates.

Self balancing is completely impossible for Li-Ion cells. There is no mechanism to transfer electrons from one cell to the other if connected in series, this is against basic laws of physics.

Despite all that the Sony V3 cells used in BionX batteries without BMS have outstanding quality and consistency.
If you buy 50 cells and plan to use them without BMS, it does matter if they have differences in capacity and internal resistance of 2%, or only 0,5%.

Ri is not relevant for drift.

Differences in capacity are possible and so you get different voltages at low SOC, but this is NOT drifting.

Driftig is the loss of electrons in single cells within a series connection. This is impossible in Li-Ion batteries (except for self discharge).

I wouldn't recommend V3 cells for BionX batteries. There are much better performing cells available today.

 

[madin88]

Thats all extremely interesting.
But by all means i will do mentioned test of charging two cells in series without balancer, because i don't think Syonyk is a lier!
One with 0,1V lower voltage as the other. I have a few new Sony V3 which leftover from BionX battery repairs.

I think any further discussion deserves it's own thread as this is not the right place here.

 

[Cephalotus]

A German/Swiss "investor-team" plans to buy the BionX motor production and offer BionX products in Europe and maybe also North America:

https://www.sazbike.de/hersteller/bionx-gmbh/bionx-stellt-moeglichen-investor-1550642.html (in German)

So there is still some hope.

 

[alisonjcw]

BionX Canada Inc.'s assets will be sold via online auction from now until August 15th. This links to the catalogue and for more info: https://www.bidspotter.com/en-us/auction-catalogues/bsccrgcre/catalogue-id-capita2-10000

 

[eCue]

These dealer oriented companies are so greedy the bikes end up too expensive to make sense and they fail. Losers

 

[MadRhino]

BionX was doing good with bike shop clients who were after pedal assist fully installed and serviced at the lbs. That was until they developped two larger, thinner motors. They were an improvement, but didn’t sell. BionX was not big enough to absorb the loss.

 

[wturber]

BionX was doing good with bike shop clients who were after pedal assist fully installed and serviced at the lbs. That was until they developped two larger, thinner motors. They were an improvement, but didn’t sell. BionX was not big enough to absorb the loss.

There's info previously in this thread that points to a different cause. That cause was a failure of BionX to deliver on a joint development project with (I think) General Motors. GM exercised a clause in their contract to reclaim a few million (four?) dollars and BionX couldn't cover it. Hence, bankruptcy.

I suppose failures in other areas could have been contributory, but they weren't the proximate cause.

 

[MadRhino]

BionX was doing good with bike shop clients who were after pedal assist fully installed and serviced at the lbs. That was until they developped two larger, thinner motors. They were an improvement, but didn’t sell. BionX was not big enough to absorb the loss.

There's info previously in this thread that points to a different cause. That cause was a failure of BionX to deliver on a joint development project with (I think) General Motors. GM exercised a clause in their contract to reclaim a few million (four?) dollars and BionX couldn't cover it. Hence, bankruptcy.

I suppose failures in other areas could have been contributory, but they weren't the proximate cause.

Causes and effects. Development investments that didn’t produce expected profits, dealer network that were stucked with inventory and didn’t engage in the next booking, handicaped the financial capacity to meet further development expectations, and drained the capital that would have been necessary to cover contract penalies.