Kingsong S20/S22 (Confirmed)

[Blunzn]

yeah not sure about my 'every cell' comment. also didn't Jack mention in some interview something like they don't know how many smartbms features they implement in the app cause not many will ppl care and check their battery anyhow.  

edit: just went through the interview at 2x speed... its at 52:10 of the video below and he said: "a deepdive of each cell" "you'll see which cell is healthy or not and the bms will tell you which pack is broken" "batteryhealth" "nobody comes home and check if their cells are ok" - so it should be able to do it but no clue if they let us see all the details or just give us a some 95% batteryhealth info.

1 hour ago, Rotan said:

I love everything of this wheel but one thing: pedals are way too high.

Motor is powerful and ht, it's not a stupid extreme speedster, battery is more then enough, design is sick. 

Those pedals though, really too high... I know that suspension wheels are higher but this seems way higher then s18 and v11. 

the pedalheight can be reduced a bit, but ofc you'll loose suspension travel.

 

 Jacks comment in an early interview about height adjustment - so you could adjust them 13mm up and 13mm down but he didn't know at what position it gets shipped. so you maybe can lower it 1 or 2cm. max 2,6cm if they get shipped in the upper position.

 

Edited January 23, 2022 by Blunzn

[enaon]

55 minutes ago, Chriull said:

... i would not interpret too much in a word from the marketing department...

 

I agree, I do not have my hopes up, mainly because they are not ready I think on the app side too, per cell monitoring needs a way for the user to monitor it, if it is kept inside the logic, it is good, but not what I want. 

But I still have hope, the s18's bms looks like they were going there, the s20 pack has extra wires, I hope for comms and info that is somehow exported to the bt level. 

[Rotan]

1 hour ago, Blunzn said:

 

the pedalheight can be reduced a bit, but ofc you'll loose suspension travel.

 

 Jacks comment in an early interview about height adjustment - so you could adjust them 13mm up and 13mm down but he didn't know at what position it gets shipped. so you maybe can lower it 1 or 2cm. max 2,6cm if they get shipped in the upper position.

 

Oh that's great! Just turned in the best euc to ever for me 🤣

[jrhz06]

1 hour ago, Rotan said:

Oh that's great! Just turned in the best euc to ever for me 🤣

Don’t forget that the suspension also compresses when you get on the wheel which will also make the pedals lower.

[Planemo]

3 hours ago, Chriull said:

If one knows every string voltage one knows each cell voltage 

Oh no not this again! 

Stop being pedantic, you know full well what I mean, in that 5 cells per string (for example) could give you 4 cells at 4.25v and one at 4.05 and give what the BMS would still call a 'fully healthy' string voltage of 16.8.

There could be a world of sin living in that 4.05 cell and you know it so stop being an argumentative old git 

[enaon]

7 minutes ago, Planemo said:

Stop being pedantic, you know full well what I mean, in that 5 cells per string (for example) could give you 4 cells at 4.25v and one at 4.05 and give what the BMS would still call a 'fully healthy' string voltage of 16.8.

 

it doesn't work like that, the string is the 2 cells in parallel.
30 strings, 2 cells in parallel  each, 60 cells per pack. 

it either has 60 measurements (30 for each pack, the way the ninebot z10 was),or it is not smart the way we need it yet. 

Edited January 23, 2022 by enaon

[UniVehje]

13 hours ago, Rotan said:

Oh that's great! Just turned in the best euc to ever for me 🤣

I got used to high pedals with V11 and actually like it now. It’s nice for touring and good for trails. 
 

Overall, looks like a great wheel. And production looks positive now. I hope Inmotion announces V13 in January as they promised. I’ll preorder after I know what, and especially when, they’ll offer. 

Edited January 24, 2022 by UniVehje

[Planemo]

52 minutes ago, enaon said:

it doesn't work like that, the string is the 2 cells in parallel.
30 strings, 2 cells in parallel  each, 60 cells per pack. 

Cool, if the S20 is only running 2 cells per string thats great. I didn't know it was that low. I was just thinking out loud (and having a pop at Chriull re strings and configs, using 5P as an example because that what the Sherman has (12 strings in each pack of 60 cells, therefore 5 cells per string) giving 48 measurements per 240 cells which doesnt sound like a lot when you think about it. Although 10P in a wheel does give a nice warm feeling (if its all working OK..)

52 minutes ago, enaon said:

or it is not smart the way we need it yet. 

In my view a BMS being truly 'smart' actually has less to do with cell count per string (although the less the better) and everything to do with the ability to do CC balancing. This top end balancing lark is crap and should be dragged out of the dark ages. For the S20 to be deemed smart it should employ such a system (which it may have, I have no idea )

[enaon]

2 minutes ago, Planemo said:

using 5P as an example because that what the Sherman has

I undersrtood, but in in any case you do not get to add voltages on the parallel strings, the bms cares not if you have one or 10 in parallel, it sees only one. 

[Planemo]

13 minutes ago, enaon said:

I undersrtood, but in in any case you do not get to add voltages on the parallel strings, the bms cares not if you have one or 10 in parallel, it sees only one. 

I never spoke about voltages?!

All I was trying to get across is that the more cells there are hanging off a string, the less ability there is to speedily isolate and identify a rogue cell. But then I am very confident you know that so I dont quite understand your post. Probably derailed this enough though tbh 

[enaon]

1 hour ago, Planemo said:

I never spoke about voltages?!

All I was trying to get across is that the more cells there are hanging off a string, the less ability there is to speedily isolate and identify a rogue cell. But then I am very confident you know that so I dont quite understand your post. Probably derailed this enough though tbh 

sorry, I got curried away, I really want per string monitoring 

[Chriull]

1 hour ago, Planemo said:

strings and configs, using 5P as an example because that what the Sherman has (12 strings in each pack of 60 cells, therefore 5 cells per string) giving 48 measurements per 240 cells which doesnt sound like a lot when you think about it. Although 10P in a wheel does give a nice warm feeling (if its all working OK..)

Strings is a bit a strange expression for cell configs as used in our EUCs. As there only exist one "string" per battery pack.

Like one of a shermans pack has a 12s5p config meaning that one has 12 blocks of 5 paralleled cells in series.

Two of such packs are connected in series, so one has a string of 24 blocks, each consisting of 5 cells in parallel.

For this 24*5=120 cells 24 measured  voltages are needed to know every cell voltage of this pack.

For both battery packs 48 voltages are to measured to know all 240 cell voltages.

So there is the same result, but honestly i cannot follow your "strings"...

So in the detail one has 48 blocks of 5cells in parallel. These are put in two strings of 24 such blocks in series.

[Tawpie]

Is a “smart” BMS anything like a Smart car or is it more like a smart phone?

It’s marketing smoke and mirrors until somebody figures what is really being monitored or managed.

As a person who wants to be able to charge this thing in my home and wants the battery to last a few years, I need it to be smart enough to take care of things so it doesn’t burn anything down, and doesn’t die an early death from imbalance. If it can pinpoint a weak cell that’s great for somebody that can repair a pack, but I’m still going to have to replace the entire pack. I need a “not dumb as a post” BMS.

[enaon]

the s18's bms is there already, it has status monitoring, fuses, mosfets, this talk is not about fires. "Smart" is more about forecasting problems and resolving them, peace of mind. 

[Blunzn]

1 hour ago, Chriull said:

Strings is a bit a strange expression for cell configs as used in our EUCs. As there only exist one "string" per battery pack.

Like one of a shermans pack has a 12s5p config meaning that one has 12 blocks of 5 paralleled cells in series.

Two of such packs are connected in series, so one has a string of 24 blocks, each consisting of 5 cells in parallel.

For this 24*5=120 cells 24 measured  voltages are needed to know every cell voltage of this pack.

For both battery packs 48 voltages are to measured to know all 240 cell voltages.

So there is the same result, but honestly i cannot follow your "strings"...

So in the detail one has 48 blocks of 5cells in parallel. These are put in two strings of 24 such blocks in series.

isn't that sherman-talk a bit OT  

how many stings does the S20 have ?

[  ] 1/2

[  ] 2

[  ] to few

Edited January 24, 2022 by Blunzn

[mrelwood]

More than the number of strings, I’m interested in whether they are attached or not!

 

[Tawpie]

1 hour ago, enaon said:

"Smart" is more about forecasting problems and resolving them, peace of mind

Ah. Monitor as the focus, got it. I’d like the charge Management to improve so that my cells are actively kept balanced and I don’t have to worry about how long to leave it on charger. I really don’t want to have to replace a battery any sooner than I must, they’re 1/2 the cost of the entire wheel. Of course, this means moving away from the relatively simple (and easier to make reliable) systems we have today toward ones that are able to do more. Which means more capable monitoring!

KS claims their roots are in BMS, so I expect them to be able to improve things.

[enaon]

28 minutes ago, mrelwood said:

More than the number of strings, I’m interested in whether they are attached or not!

there is an Ancient Greek writing that goes like:
 

"hε ωho rιdες ιnμoτιon, σhoυλd joκε aβouτ ks noτ" 

[Planemo]

8 hours ago, Chriull said:

Strings is a bit a strange expression for cell configs as used in our EUCs. As there only exist one "string" per battery pack.

I use the term 'string' to define any cell (or in our case usually a group of cells) which has it's own voltage, charge and any other monitoring circuits.

8 hours ago, Chriull said:

Like one of a shermans pack has a 12s5p config meaning that one has 12 blocks of 5 paralleled cells in series.

Two of such packs are connected in series, so one has a string of 24 blocks, each consisting of 5 cells in parallel.

For this 24*5=120 cells 24 measured  voltages are needed to know every cell voltage of this pack.

For both battery packs 48 voltages are to measured to know all 240 cell voltages.

You're confirming what I said. Ultimately, the example has 240 cells, but only 48 monitors. Whichever way you look at it, in an ideal world thats not enough monitors.

I know you're trying to get across the idea that a string (or monitor) should be treated as '1 cell' as there is only 1 voltage being measured. But we're not talking about single cells, the reality is there are multiple cells on one string. Your idea would work if we were for example using truly single cells at say 4.2v/17,500mah. We could then use 48 strings and monitor each and every individual cell. As soon as one cell gets iffy, we would know immediately. But when we are grouping 5 cells on one string more time can pass before a problem shows up to the BMS (too late in some cases) due to the potential 'OK but not' situation of 4x 4.25v/1x 4.05v and even when it does flag up we don't know which of the 5 cells it is until the group is split down and each cell individually tested.

I'm not sure if I can make it any clearer, maybe we need to split this discussion

[Chriull]

1 hour ago, Planemo said:

But when we are grouping 5 cells on one string more time can pass before a problem shows up to the BMS (too late in some cases) due to the potential 'OK but not' situation of 4x 4.25v/1x 4.05v and even when it does flag up we don't know which of the 5 cells it is until the group is split down and each cell individually tested.

5 cells in parallel always have the same voltage! 4x4.25V and 1x4.05V is not possible.

They can be in some a bit different states of degradation (overall capacity, ...)

But they die together and normally none of these 5 cells can reasonable be saved. There is no real use in disconnecting them again.

It's just with e cars like teslas with much more cells which have many cells in series paralleled. So one can automaticly disconnect such cells in series once they degraded.

1 hour ago, Planemo said:

I'm not sure if I can make it any clearer, maybe we need to split this discussion

Maybe with use of "parallel and in series" it gets easier - then it's a clear description. Using string for paralleled cells still makes me shiver- maybe because i'm no native english speaker....

[Planemo]

7 minutes ago, Chriull said:

5 cells in parallel always have the same voltage! 4x4.25V and 1x4.05V is not possible.

Yes but my point is that voltages can rapidly change when those cells are isolated. The BMS cannot identify a bad cell within a group of 5. Yes a bad cell can have the same voltage when it's grouped with another 4 perfect cells, but isolate the bad cell and it will quite easily show up. Example - I had a group which as far as the BMS was concerned was no problem because they charged to 4.2v total, but I had my suspicions. After splitting the group into individual cells one of them dropped voltage compared to the others even just sitting on the bench. The bad cell wasn't holding charge even after a short time and with zero drain applied to it.  As an aside, it WOULD still charge to 4.2v, thus no issue as far as the BMS was concerned. I ran tests on the other 4 cells and they all performed as expected. The bad cell couldn't even provide half the performance.

7 minutes ago, Chriull said:

But they die together and normally none of these 5 cells can reasonable be saved.

I disagree as per the above example. They don't have to die together and the other cells CAN be saved, but only if the situation is caught early enough which most BMS' can't do, and the problem becomes worse the more cells that are in a string because the good cells mask problems and prop up a bad cell for a longer time period before problems are noticed by either the BMS or rider. It's this length of time that is concerning (rather than the hassle of replacing a cell) because if left long enough a cell could go nuclear before any real symptoms presented themselves to the BMS.

7 minutes ago, Chriull said:

Maybe with use of "parallel and in series" it gets easier - then it's a clear description.

For me, the terms 'parallel' and 'series' are in no way associated with 'strings'. Eg you could have a 4s5p pack with zero strings if there wasn't a BMS used. A string is simply a BMS control wire.

It's all a bit moot because until we get huge capacity/output single cells (which would mean each one can have it's own string) we have no option but to clump groups of cells together and monitor them as whole, hoping they all stay happily shaking hands.

[RagingGrandpa]

On 1/23/2022 at 4:33 AM, Rolzi said:

 

No cell frames?!?
Oh dear...

 

[Rawnei]

Looks like a gray/semi-transparant frame to me ?

[btl]

A delayed wheel can finally be awesome, a rushed wheel will forever be flawed...

I love that battery mounting video. Looks more and more like a very matured product.

[nosamplesplease]

41 minutes ago, btl said:

A delayed wheel can finally be awesome, a rushed wheel will forever be flawed...

I love that battery mounting video. Looks more and more like a very matured product.

It looks like a safe place to put a battery. But that battery itself should not be handled by the end user, ever.

It belongs in a protective case that does not flex, SOMETHING needs to protect that battery from the metal chassis. Any damage or dent to that metal is a threat to the battery.

Lithium cells don't like to be punctured.