Why not, just build a bigger battery...?

[ZenExMachina]

So, yes, I'm new here and don't officially have my Begode Master in hand yet, but I have built plenty of batteries, so my question with regards to the Begode master that's using the Molicel batteries is, why not just add more P groups?

This question is really directed to anyone that is a battery builder here that has experience but I can't for the life of me figure out why we can't just build our own 8s6p batteries instead of 8s 4p batteries and go beyond what is listed on the comparison table for the battery configuration. And get more distance out while not sacrificing power?

ALSO, why not just use waterproof electrical disconnects at the edge of the housings to have the batteries removable for hotswap, instead of running the cables internally/directly to the board.

Im honestly thinking of doing this before even riding on it; I have a bunch of plans to reduce weight with carbon fiber anyway that will take me a couple of weeks.

Am I missing something here?!

[Planemo]

5 hours ago, ZenExMachina said:

So, yes, I'm new here and don't officially have my Begode Master in hand yet, but I have built plenty of batteries, so my question with regards to the Begode master that's using the Molicel batteries is, why not just add more P groups?

Space. Most modern wheels are stuffed already. Unless you are talking about adding external packs but that brings other problems obviously. Theres not a lot of place to put them where they wont get in the way of the rider.

5 hours ago, ZenExMachina said:

e waterproof electrical disconnects at the edge of the housings to have the batteries removable for hotswap, instead of running the cables internally/directly to the board.

Easily changeable batteries may be handy but you would still have to dismantle something in order to get the packs out whether you have external connectors or not. Bear in mind also that most folk just don't need swappable batteries, a fast charger is usually enough to give a full days ride and far easier to carry than another 3000Wh+ pack.

[techyiam]

I don't have a Master, nor am I a battery builder.

I am just judging from what I have seen of the Master. If you are able to find room to mount the larger enclosures that will house the 8s6p packs, and understand how Begode wired the battery packs, I think it is doable. Not sure how it would ride though.

I suppose you would have to replace the OEM pads, and what not to fit the bigger packs. Nothing insurmountable I suppose. At least there isn't a plastic shell to constrain you.

[meepmeepmayer]

10 hours ago, ZenExMachina said:

Am I missing something here?!

No, you are completely right and reasonable.

Never ask why manufacturers do not do some obvious thing. You will just slowly go mad. Because there are no good answers, that's just how they are. Well, there is an answer, same as here, but it doesn't help anybody, that's why you quietly roll your eyes when they do their latest "but why not just ...?!" thing and try not to be bothered too much

As for the general idea, a Master/EX20S successor which might essentially be a Master with bigger battery is what a lot of people are looking forward. I am at least.

In principle, you could replace each of the Master's four 8s4p packs with an 8s6p (or even just 8s5p) pack and the wheel wouldn't be any wiser. The unique and strange battery config of the Master (again, don't ask why lol), with the packs in series, means you cannot just add extra 134V packs, but have to do it this way by modifying each existing pack.

I would get your wheel first (it's a great wheel by all accounts), learn to ride, and then you will know what you want to modify.

Edited July 17, 2022 by meepmeepmayer

[ZenExMachina]

Thanks everyone for the feedback.

@Planemo @techyiamI'm with you, most are indeed already stuffed, which is why the idea is to completely replace the battery packs with larger 8s6p packs.

As for the quick-change aspect, I was actually thinking more of riders who hit trails. Nearly done with a pack from riding hard but not done for the day? Maybe you brought your car to the location and have the packs there to switch out and keep riding. At least that was the question behind my initial question. For commuters, I'm with you, makes no sense and you can just keep a charger at work if you happen to forget charging overnight and make it there by the skin of your teeth.

As for the padding? For sure a replacement as well, I really don't think they're designed well and I'm very impressed by the fairing system that Clark Pads developed, will def be designing and printing my own PETG system as well.

@meepmeepmayer I'm a manufacturing engineer by day, so I know exactly why they wouldn't do something: Money! 

I'm just befuddled by the lack of 3rd party R&D when it comes to modifications more serious than the variety of pads people/companies are competing on. (E.g. Clark, Kai, etc.)

If the Master successor really is just a bigger battery, ya'll can miss me with that ish. I'm hoping for more from he next generation. If these companies are advertising to EU and West (since it doesn't seem like EUC is as much a thing in China), they should know that the average weight for people in more obese countries are going to be higher, which means stronger suspension systems from the get-go, not having to modify with a Fox Shock like Roger on YT did to get decent suspension without bottoming out.

As for the battery config, I'm down to completely replace the batteries, but when you say I have to modify existing packs...well I guess I'll just have to find out when I get it in hand and tear them open.

I know I'm putting the cart ahead of the horse; I've never ridden in my life and I'm learning to ride an EUC on an unbroken-bronco, but these are the kinds of questions that tickle my brain and go "wth, why is no one SELLING this?" CF replacements for battery housing aren't as expensive to manufacture by hand as people think, and with a little kevlar for electrical isolation, that would ease a lot of people's worries about naked frames that have (essentially) exposed battery packs like the Master.

[meepmeepmayer]

2 hours ago, ZenExMachina said:

If the Master successor really is just a bigger battery, ya'll can miss me with that ish.

That is pure speculation. Just what we reasonably can expect - 134V like the Master, but with more battery. 3600Wh is natural and a size found on 100V wheels already, so it seems logical.

2 hours ago, ZenExMachina said:

I'm hoping for more from he next generation. If these companies are advertising to EU and West (since it doesn't seem like EUC is as much a thing in China), they should know...

Everyone wants more from the next generation. They (the manufacturers)  should know, but they just don't. In many respects they are genuinely clueless.

Like I said, don't frustrate yourself too much thinking about this, it is how it is. But if you plan a lot of DIY mods, that is already the right direction to get what you want.

2 hours ago, ZenExMachina said:

As for the battery config, I'm down to completely replace the batteries, but when you say I have to modify existing packs...

You don't have to modify, just when you don't want to waste the existing packs you paid for.

I doubt that the board sees anything but the voltage coming from the battery side. Which is 134.4V from four 33.6V (8s4p) packs in series (so far). So you can't just easily add another pack, as in principle you can with any other wheel where the packs are full voltage and in parallel like God intended Now how you add battery capacity is up to you, this is just the state you begin with.

2 hours ago, ZenExMachina said:

but these are the kinds of questions that tickle my brain and go "wth, why is no one SELLING this?" CF replacements for battery housing aren't as expensive to manufacture by hand as people think, and with a little kevlar for electrical isolation, that would ease a lot of people's worries about naked frames that have (essentially) exposed battery packs like the Master.

The custom battery thing is new, ewheels started it. People would surely buy alternative battery packs for more capacity and per-cell monitoring and whatnot. One cannot currently buy wheels without their batteries, though, which might be an impediment. The batteries are probably the bigger part of the overall price, so custom batteries should replace the stock ones, not have to be bought extra. The best way to get what we want here is pestering influential dealers (ewheels), who have the ear and clout with the manufacturers.

The Master's packs are foil packs, cushioned with foam, inside their plastic boxes. They should be robust enough.

One issue to keep in mind with detachable battery packs is that people might connect them back when they are at different voltages. That's a big reason you cannot just easily have swappable battery packs and only expect sunshine and fluffy bunnies, it needs some more thought on how you would do it precisely without disaster.

But since you are going for the DIY mod route, your imagination (and budget, I guess) is the limit for what you can do. Begode wheels are simple and the most easily modifiable.

Edited July 17, 2022 by meepmeepmayer

[Whalesmash]

Begode's latest offerings in both the EX20S and Master are both very modular. It's partially why everyone is expecting them to release a 134V version of the EX20. Realistically it should be very easy for them to do, considering all they need to do is shove the master's power distribution board and motherboard into the EX20 carcass. The only bit of engineering required would be to rework the 100V 900WH packs into suitable 134V layouts. I don't know much about batteries, but I don't imagine this to be too difficult. TLDR, yes, OP you are correct, it's not too difficult for begode to increase the battery size of their current offerings. We'll probably see something along those lines in the near future anyways.

[yoos]

Some remarks:

1. Serious aftermarket R&D is still not worth it: the market is still relatively small and heavy weight and battery hazards hinder shipping back and forth between customers and aftermarket workshops, so it has to be local enough. Furthermore EUCs still change significantly from every few years so you don't want to spend a year of development on building the perfect upgrades for a particular model that will be outdated soon (people who want mods and upgrades typically also want the latest or at least bestest)
2. Nevertheless there are people who offer meaningful aftermarket upgrades, including battery replacement or even extension, improved hard parts (pedals, hangers, shells), extra capacitors, custom cooling and so on. Most of these services can be adjusted to fit newer wheels. However, deisigning an overhaul upgrade with swappable batteries might be too much.
3. Why have swappable batteries if you can have a swappable EUC? After all the battery seems to be the most expensive part anyway. Swapability adds extra intriciacies and manufacturers are currently struggling to deliver consistent quality even with basic non-suspension models. It also adds the problem of balancing between packs of different state of charge: things the average consumer does not want to bother with (or you have to offer an advanced charging and balancing station to go with the EUC). Most customers are happy with the single pack of batteries and don't want to pay extra in terms of money, weight and volume for the option to swap batteries if they ever decide to shell out an extra 50% cost of the EUC for backup packs.
4. An overarching problem is that once you get into high range and high velocity the EUC starts to lose to multiple-wheel vehicles on all fronts (except magnificence which is a question of taste). The EUC really shines as a dense-urban-environment vehicle -- it literally beats most alternatives with the combination of agility, versatility (it can keep up both in the street and on the sidewalk) and portativity (trolley into shop, shove under your chair, keep inside apartment, no parking required). In other environments (off-road, highway, rural area) it is still wonderful but you have to really love it to choose it over other options. The edge of todays performance (represented by the Master, Sherman, S22) is already a tad beyond the optimum (where EUC beats all else) in my opinion -- typically too heavy and the high speed compromises safety and requires a long gear-up session before riding. It still has its solid customer base but that's not where the big money is (the money sits at the V8 level of performance)

[alcatraz]

If you could build a 32S2P and hook up in parallel with the existing 32S4P (split into 4) you'll achieve that 32S6P you want. Then you can go with low current cells and get that massive range. Sure.

Quick connects would need to be heavy duty. I've seen what happens to bullet plug motor wires when the connection isn't great. They overheat like crazy and melt everything around them.

You don't want that so connectors are all beefy, solid copper, and cells are spotwelded together.

If it weren't necessary we could have cells mounted like in remote controls. Easy swap. 

[alcatraz]

I think that for safety reasons one day vehicles should be offered without batteries and then the packs come from somewhere else that guarantees them. Fully specced smart bms' and service network etc. More configuration choices etc.

[alcatraz]

I'm working right now on an external pack for my MSX84. It's pretty massive at 10kg and 2600Wh. End result is 4200Wh and 33kg. Pretty slick, huh.

Got it at an amazing deal too. It's a diy pack made from Panasonic Tesla motor cells 21700. 100USD for 2600Wh. I need to buy a smart bms for it which is like 30USD here in China. Bluetooth, active balancing (no bleed resistors), the works.

[ZenExMachina]

@meepmeepmayerYou're absolutely right. I don't think you're making too far of a leap assuming that that's the next level that will be available for Begode, since its already been proven. And I really shouldn't be wasting my brain power, I know, especially because EUC is already a niche within a niche (PEV), guess I'm just one of those people who finds a hobby and then likes to scream at the sky, then return to my new hobby.

@yoos You make some excellent points, thought I'm still new to the hobby and am not familiar with 3rd party hangers, shells, extra capacitors, custom cooling, etc. You got links you can share or is this all Facebook type stuff? Also, touche regarding just swapping your EUC. From a cost perspective, it still seemed to me less to have an extra set of batteries than a second wheel, but I suppose if you're already bringing a car to a location, you might as well bring a second wheel to ride on.

Regarding your 4th point though, what do you mean? We talking like, increased weight, speed, power, etc, like compared to an e-scoot-scoot et. al, might-as-well-be-using-one-of-those?

@alcatraz Sweet you were able to get such a deal for those Panasonic 21700's. How are you planning on mounting (or backpacking?) your external battery?

[alcatraz]

First I'll strap it to myself, then after my feet start hurting, I worry about such things hehe.

[yoos]

5 hours ago, ZenExMachina said:

You got links you can share or is this all Facebook type stuff? Also, touche regarding just swapping your EUC. From a cost perspective, it still seemed to me less to have an extra set of batteries than a second wheel, but I suppose if you're already bringing a car to a location, you might as well bring a second wheel to ride on.

I am mostly aware of russian workshops. Most of them have successfully done business with overseas customers, but I am afraid the war has made it difficult to continue (but you may ask them -- they are definitely friendly and [I believe] pacifist). https://eucmarket.com ("Alexa" is also part of it), https://www.instagram.com/eucyou/?hl=en, https://www.instagram.com/eucyou/?hl=en. There are also @iCafe in Stockholm who offers overhauled EUCs, https://eucservice.com in Poland who also does very deep modifications. This is not a balanced overview, just a few names I know second-hand. I only have seen eucmarket wheels in person and they are flashy.

To design all the options like swapability etc the market must become larger first so that every modification will have enough buyers and the cost to develop and set up production of all the variants will be negligible. It' already great that manufacturers and distributers now offer the same wheel with different battery options.

5 hours ago, ZenExMachina said:

Regarding your 4th point though, what do you mean? We talking like, increased weight, speed, power, etc, like compared to an e-scoot-scoot et. al, might-as-well-be-using-one-of-those?

Yes. If you are riding at high speed this means that 1) your vehicle is heavy 2) you have to keep large distance 3) you can't make sharp turns. This means that the single-wheel setup does not offer much benefit compared to a two-wheel regarding weight, size, maneuverability. At the same time two wheels offer much more safety because if the controller/battery/motor fails you can still coast on a two-wheel vehicle. That's the gist of it: at high speeds an additional wheel brings much safety and stability without sacrificing much. You can also see this comparing EUC specs with scooters. At 17kg, you have a MCM5 with 45kph and good range, while a scooter of the same weight goes slower, has less range, has smaller wheels, is bulkier and requires more maintenance yet commands a comparable price. The choice for a city lurker is obvious. At 35+kg and 2500+$ it is less obvious.