it's not learned in-house, they've got users as cannon fodder

FrenchUsa what battery configuration you have?

@@Papalou1234 2400 Samsung 50e, this battery is good for long range.

I am glad you slow down and good to hear feedback from yourself Master riders. Thank you.

That is what I thought as well you’re the first one reply with this idea. Well done.

@@eucupgrades Could this wheel be modified so that it is in this parallel configuration? Or would that break the wheel?

@@arronnie1 no you wouldn't be able to do that because running in parallel would make it a 34 volt wheel and it would not run off that power

That's not true that each cell will bear a higher current load. Each *_pack_* will bear a higher load than parallel packs would, but the series pack still spreads the current across 4 parallel cell groups (the Master's packs are 8S4P, where 4 8S4P packs in series yields the 32S4P 134.4V configuration). I don't care what Dr. Lewin says, Kirchhoff's law holds 😂 That said, I'm not sure what the degradation of a bad cell looks like in this configuration, and I don't know how the parallel groups are connected inside the new packs. Assuming that the other Begode batteries don't just completely disconnect during a "failure," this new battery configuration would yield a similar situation where a failed cell group causes the others to "pick up the slack." Still a dangerous situation either way that would need to be addressed with urgency. The points of failure at the series connections are certainly something to keep an eye on - definitely check those solder joints. Similarly, a cable failure would be a complete system failure.

@@redfoxdude Eh, I don't see your first point. I'm fine if I'm proven wrong, always good to learn something new, but then your explanation is lacking. This wheel is rated as an operation 134V 32S, ie. true parallel count is 32 cells per parallel, not some subdivision of 8, otherwise you're running a lower operational voltage is my understanding. Are you trying to say you can just subdivide down to any mix of number series physical packs? Then why would you ever limit yourself to whole full 24S 100V or 20S 84V packs, which has limited EUC designs for the past 8 years due to space constraints, sometimes weird bridging of small packs wired to the main pack. And my higher load point was inferring that there is higher amp load per cell vs if you had another True 32S 134V parallel pack in-line, so that the load is spread across like 32S2P / 64 cells, vs the Master 32S1P / 32 cells, ie more True 32S Parallel. I was NOT saying that there was more load per cell on this 4 subdivided configuration vs a true whole 32S1P pack same number 32 cells.

@@houseofjob Ah, I see the misunderstanding. I agree that 32S1P would yield very high strain on the cells. However, the Master is not 32S1P - it is *_32S4P._* Each individual pack is _8S4P._ (For clarity: 8 cells in series gives you the 8*4.2V=33.6V pack voltage. 4 packs in series gives you the 8S*4 packs=32 series in total for the 134.4V system voltage.) There are a total of 128 cells in the Master, so each pack has 128/32=4 parallels inside: 32S4P. (EDIT: For some extra clarity: we can calculate that there must be 128 cells. The listed capacity is 2400Wh. The 50E cell has approximately 18.5Wh (3.7V*5Ah). 2400Wh/18.5Wh = 130, where 128 is the closest common multiple of 32, 32*4. Thus, the Master is 32S4P.) So it's a 4P like in the RS for example, in terms of the distribution of load across the cells. Each of the two RS packs have 2P, and two of those in parallel gives you 4P in total. As for why you would limit yourself to full packs, my main guesses would be cost and build complexity. It's been helpful in that way for Begode for reuse of the same pack in multiple EUC models. Otherwise, I'm not really sure. The Sherman splits each 100.8V pack into two 50.4V packs on either side.

@@redfoxdude I see. This is a better explanation yes, thanks. I forgot about the 128 total cell count, distracted by this foreign concept of summing the 4 physical packs to make the full 134V. I think the Shermona is a different beast tho no? it bridges the gap of BMS connect / split BMS, with a wire that only goes between the 2 adjacent packs, ie. no mix and match possible, no connecting of this communication wire to the XT60 or XT90 termination at the board, no using each pack independently. We had an engineer rider friend who was has since passed, who tried to explain something similar to this, splitting of Series count to sum as a bigger operational voltage, but I'm still admittedly struggling to wrap my head around that. If you have any online resources about this and could link, I would much appreciate it! (and thanks for the reply).

@@houseofjob Yeah, the Sherman's series packs aren't fully independent like the Master's - they have BMS connections between the series packs, like a split BMS as you described. I'm sorry to hear about your friend passing. I'm an engineer (electrical) too. Totally happy to chat about this kind of stuff, engineering is both my profession and my hobby =) As far as splitting the series count (ignoring parallels, let's consider any parallels as if you just have a single cell with higher capacity), when you follow the path of electrical current, say from battery (-) to (+), each time you pass a lithium cell in that path, you get a voltage boost (+4.2V if at full charge). The electricity flowing through the cells along the path doesn't care where you place the battery housings, if it's still along the same series path, you still get the same boost. So putting another pack in series, you add more cells into that series path, adding even more voltage. I don't have resources right off hand, as I am going off of my knowledge from stuff like nodal analysis. I don't wanna link that stuff though, way too into the weeds, ha! I did find this, which looks like a decent go at it: batteryuniversity.com/article/bu-302-series-and-parallel-battery-configurations

I imagine a bad cell would manifest itself in a similar way too, making its parallel brethren take up the slack. It wouldn't make the wheel shut off, but would be similarly dangerous as in a parallel pack configuration. What we need is for the pack to be able to report when a parallel group is sagging below safe thresholds and trigger something like an overload warning and tiltback...

@@redfoxdude agree. Neither of the configuration can be safe for riding and fire until individual cell groups are monitored, and the mainboard is informed of pack issues to prevent riding.

Most people wouldn't do that. I'd prefer they design for the rule, rather than the exception.

Begode said it is low voltage which is easy to manage and of course low voltage is less dangerous. with that many battery cell gives you more Amps on one pack. Adding all 4 battery together to give 1900wh and 134v. The only danger part is the charging circuit the holds the 134v and i have already have one gone wrong which doesn’t charge the battery.

thanks.

Theoretically, from what I understand from the video, if a single pack yields in one way or another you will hit the asphalt. 4 packs = 4 times more likely to fail. But until we find out exactly how those packs are built inside, we don't know for sure.

Yes. Just remove the top cover and 4 screw that hold the battery pack and unplug the pack.

Airbag! 😁

Better battery chemistries are coming. Until then we will have the danger of fires!

I think the peak power is the same regardless of parallel or series battery connections. The redundancy is good if any of the battery pack is malfunction, but usually that would not happen during a ride, so I think the pros of having a lower Amp system through the wires might help reduce the likelihood of fire. But if the fire is induced within a single battery cell which will have a run away effect, then we are talking about having a better BMS, which KS might have an edge. However it seems lower Amp system is better than having a better BMS (as per the latest KS fire incident showed). I am not sure which one is more effective in fire avoidance but my bet goes to having a lower Amp system.

@@FastRadioBursts I agree but the series packs in the master carry the full current draw so the wires that connect each battery to the next needs to be able to handle it, to me they dont look any bigger than a parallel system like the kingsong , then again the wires going to the controller also carry all the available amps and they seem to be the same size so it should be ok if begode engineers have done their job right

@Mike Y "if Begode did their job". Which worked great so far.. It is such an early tech and I doubt that all these manufacturers have the needed understanding of the components used. But following the scene for a while, I'd rather have a low amp begode for sure. If I'd even buy a master. Maybe a 3rd gen with improved range.

So now if you choose between the S22 or the Master, you have to choose between the potential of an explosive fire or a face plant. Hmmmm.....🤔

Maybe they just used passive balancers.

In this configuration, balancing between packets is not necessary I think.

@@pawelkolaska1398 -these 4 packs in series definitely need balancing, otherwise they'll drift in voltage like anything made of cells in series does.- -I'm hoping for an active balancer here to handle more balancing current.-

@@pawelkolaska1398 Actually you're exactly right, it is not needed in this configuration, I missed how it works previously.

@@supercurioTube So what what middle connection do ? It is middle point between 4s+4s ? I ordered mine master and thinking how to make it safer.

Even so, I believe that the voltage will drop too much and the wheel will no longer be able to keep its balance, especially at high speed.

Only way to find out is to jump one connector and see if the wheel still works.

This is a great point; what does "a battery pack fails" mean exactly? It's not well defined here. A connector comes loose? Does that happen? A cell dies? The whole pack doesn't go... The pack explodes and a sufficient number of cell connections are severed to kill all 4 parallel 33.3v stacks? I don't know, I'm unconvinced that this is actually a riskier arrangement.

It appears that Begode wired the battery connectors in series on the control board. If you disconnect a battery or a pack develops a broken connection (not a short), then it will break the connection and give you zero volts.

@@RonNadeau I think everyone understands that, what's less clear is the odds of that actually happening. Breaking the connection of a battery without simply unplugging it involves some pretty substantial destruction because of the four parallels inside the pack.

If you do that the remaining two battery will only be 66v which the wheel will not work. All 4 batteries added together give you 134v to work.

All High voltages in parallel is extremely dangerous. This is what the challenge is for the faster wheel and how they are going to make it safe.

With one wheel device we are riding on any extra power are always better. But don't forget Begode keeps changing things on their wheel. So higher power battery mean they have to change the power circuit to take the extra power.

S22 smart BMS will be able to detect abnormal cells to prevent fires during charging. The problem with fires while charging is from "dumb" BMS trying to charge stubborn cells.

No! 33.6V for each pack, means 33.6V x 4 packs = 134.4V

I buy the Master because of Begode's self sacrificial philosophy. It would risk damaging itself trying to protect the rider in a tricky situation. Other brands don't do this. Greater risk of injury.

Also, the S22 is unsuitable for racing. The Master can do it but only on high current cells. For racing wait for the RS134V.

The reason a battery ignites is due to a buildup of internal resistance causing heat to exceed ignition temperature of the electrolyte. Internal resistance buildup is caused by manufacturing defect or inaccurate passive balancing by the BMS. You cannot visually inspect buildup of internal resistance - only an Active balancing BMS can do that.

@@RonNadeau Heat usually leaves traces. Messed up heatshrink, unbalanced voltages. If you're worried about heat then step 1, Don't get an S22/Master with high capacity cells 50E/M50T/M50LT. Step 2, Install heat sensors within the packs, and a display on the wheel. Being afraid to do a deep inspection is only going to reduce your chances.

@@mikeh6286 You won’t see traces of heat due to internal resistance on the outside of a 50E cell until it ignites. There is no pre-warning without monitoring the internal resistance with a good BMS. Active balancing BMSs are more expensive and that is why companies like Begode cheap out. I have written to them to say we would gladly pay a few hundred dollars more to get better safety with quality BMSs. Overcharging cells with Passive balancing is what is causing most of the fires.

It's probably the same becausethere's no space to fit the extra cells needed to do paralleled packs. It's likely a 32s3p 40T cells 1440Wh. Two 16s3p packs in series.

Hahaha hilarious

True all battery pack can catch fire what make it safer is the voltage output is lower and it is safety to control and manage.