After pulling down, measuring my battery pack and individually balancing the pack (see this blog post) it seems that its now working properly (which I don't think its done since new, certainly not after the first few weeks as this video I did back in July last year shows).
After that I thought I'd clear up the ratsnest of untrimmed wires from the loom left by the battery assembler (I don't blame them too much because I bet they're not well paid).
Firstly I thought it looked a mess and secondly I wondered if it somehow contributed to the problem with balance charging because of the different resistances with really long wires (and some were not).
I manged to get it like this:
before packing it up and shoving it all back together (like a swollen suitcase).
Then once all the stuff was back and the cables neatly arranged I put it on the charger and was greeted by -->> Balance Charge completion! YESS!!
So now I'm sort of stuck for what was the solution, because clearly the BMS does not have a problem now, although it did before. I'm left with a few theories:
- Somehow the pack got out of balance at some stage and was sufficiently out of balance that it was beyond the capacity of the BMS to bring back. If this is so then my manual balance charging of bundles may have been the required solution.
- Although all the solder joints looked good, perhaps unplugging and replugging the BMS (as well as point 3 below) was enough to get it working right?
- Because I shortened the wires (trimmed quite a lot off some) perhaps this made a difference too?
I really don't know, but now I'll be keeping an eye out for it.
Conclusion
Well I really would not have been able to diagnose this was a problem without in the first instance the voltmeter built into the scooter, and being able to observe the instant voltage drop when removed from the charger. Then the 150A inline monitor has really been very helpful in plotting and understanding the last phases of current draw >> after the red light has gone green << when people would think "charging is done" (see this blog post).
Either way, I'm pleased its all together and going :-)
PS: I took it for a quick spin around my usual circuit (both cycling and scooting, its a nice little run in the morning) and it returned with a good state of charge. The GPS data for it was this:
which is actually not too far away from what my Dual normally gives me:
which is pretty much what I've usually found when I initially began comparing them:
- the dual motor climbs hills better
- on the flats they're pretty similar, but the take off on the 500W single motor is much more even and gentle.
Post Scriptum
After charging the pack did not come back up to 54.7V, but 53.4, so something is amiss. This means I'm going to have to do some more testing and perhaps try one of my new BMS units. Also, a little web searching revealed this test on what appears to be the same batteries. I think its reasonable to believe that they are more or less the same as the cells that are in my pack. His conclusion was:
ConclusionPost PS: this actually fixed the BMS charging issue but did not fix the issue entirely so see my post here.
The cells looks fairly good, they are obvious not for 30A, but 20A looks fine.
: this actually fixed the BMS charging issue but did not fix the issue entirely so see my post here.
32 comments:
Thanks for all the valuable info! I bought a used dual motor 2018 widewheel (8.8aH) and I have the same issue as you described (fully charged battery = 52.5V). I carefully opened the battery to see what amp rating the BMS is. Unfortunately, half the sticker had the ink dissolve away, so it only indicates "13s". The BMS card has the same printed part number, "SN_BZ_BMS_13S_D30C30_4260" as what's shown for your single motor widewheel. I'm assuming that the "D30" indicates a 30A continuous current discharge because I have two 15A max controllers in parallel.
Can you tell me what the sticker says for the original BMS amperage rating?
Sorry, I already threw it away. I can recommend the one I have and its common on eBay and cheap too. Did you read about it in the other battery posts?
I hope you're reading this by computer not phone, which presents blogger much better than a phone.
Best wishes
No worries and thanks for the reply! I asked Eloi from Apollo Scooters and he sent a snapshot of the BMS, which is 40A (found both of your thru youtube). I'm assuming that the continuous discharge current is the same for both single- and dual-motor because the same part number was printed on the BMS.
Yup, I saw your other post with your cool 20A BMS! That seems to be the way to go, but I couldn't find a similar one at 40A. I found a different brand BMS at 35A that I will try, which should be enough for the two 15A max controllers.
I have also purchased an off-the-shelf 48V 12aH battery to replace the original. It unfortunately came with a 15A BMS, so now I am considering two options:
1) Replace the BMS with a 35A - 40A BMS and use it to run both controllers
2) Mount a second battery to the steering column, so I would have one dedicated battery for each controller (10aH, not 12aH due to a cool bag I found that will fit the battery). I am curious if a 15A BMS is enough for one 15A controller because the golden rule seems to be to use a higher current rating than the required load (due to tolerances?). If not, then I will replace both with the same 20A BMS that you are using. Equivalent total of 20aH if charging both batteries at the same time.
Any thoughts? And yes, I am using a computer. I'm one of the few in this world with a flip phone. Old school, brother.
Hi
thoughts:
Interesting, that the BMS fitted standard to the 12Ah battery would be so low. Still I don't think it is likely that will be any significant issue because so far I've not ever experienced any BMS shutdown on power delivery on my Dual. So:
1) I don't think that a bigger one is needed, but if you have it why not?
2) I do not think anything mounted on the column is a good idea, I've seen fucked up columns and I notice i) they are super thin ii) they're easy to rip once they start going because they're thin aluminium.
3) I've not used the BMS I've got on a dual motor yet, but I suspect that's in the future.
I'm not clear what you mean with the "Equivalent of 20Ah if charging both batteries at the same time ... but I guess its not important. I am not comfortable with using piggy back batteries.
Sorry for the confusion, but the 12aH battery I purchased is not from mercane and is a generic rechargeable 18650 battery pack. The dual's mercane OEM battery with the 40A BMS should be plenty for the two 15A controllers, so I wouldn't expect any issues with power delivery.
1) I am curious why they chose a 40A BMS instead of a 30A. Generally the price increases for higher current rated BMS's.
2) I checked how much weight I would need to add to the steering column for the extra battery and it's +5 lbs (+2.3 kg). It would be mounted low to the pivot point to reduce stress on the aluminum columns, but it still seems too heavy. Where did you see these damaged colums? What were they trying to mount?
3) I'm not sure if there are adverse affects of using a battery with a 20A BMS to power a 30A load (two 15A in parallel). Would it overheat from too much current draw?
Yeah, I wasn't clear enough when I stated "equivalent of 20aH". I meant that the time between charges would be equivalent as if the two batteries were wired in parallel. In this case however, the batteries are not wired together in parallel, but each separately powering one controller. Our current dual widewheel battery differs from the single by having one additional XT connector (& two additional leads soldered on BMS output) for the second controller. If you unplug the front motor controller from the battery, then your dual runs as a single (rear motor controller also handles the lights and voltage display). Quite literally, one dual widewheel is two single widewheels. This is why the dual's acceleration is screwed up because it has one throttle for two controllers.
I'm assuming by "piggy back" you meant wiring in parallel, correct? Yup, I agree it's not good because the two batteries will be balancing each other quite frequently. In other words, they will be charging each other quite frequently, so life may be compromised. I guess that is why I appreciate the simplicity of the motor/controller/battery setup of the widewheel.
Thanks again!
Hi
> but the 12aH battery I purchased is not from mercane and is a generic rechargeable
ahh ... well as long as it fits
> Where did you see these damaged colums? What were they trying to mount?
some on reddit, some at a dealer. I believe the issue is the amount of weight the rider pushes on the column, the battery itself is not a significant issue. Just make sure the two together aren't "additive"
>I'm not sure if there are adverse affects of using a battery with a 20A BMS to power a 30A load (two 15A in parallel). Would it overheat from too much current draw?
myself I'm also not sure, but my observation is that the BMS does not carry the load of the discarge, for if you look at the wiring its directly to the battery with a 2 wire BMS and even if the the BMS does carry the load its a small amount of watts (which is what generates heat) The voltage drop will be under a volt from the BMS and so even 1V x 30 amps is only 30W ... so not much heat.
>I'm assuming by "piggy back" you meant wiring in parallel, correct?
I was meaning plugging the other battery pack into the charge port of the scooter (which is intended to charge the original battery, not to act as a parallel supply port)
Yup. The battery choice was solely based on cost. A 12aH mercane battery is 450USD direct from a vendor and 350USD from ebay. Sweet fancy Moses. And what's with that long black wire soldered to the four batteries on the side? That can't be good for cell balancing. I'll let you know how the new battery works out.
Wow! Damaged columns from the rider's weight? Maybe they were doing jumps at a skate park. I tend to ride the widewheel similar to a skateboard with as minimal use of the handle bar as possible for balance. From this approach to riding the widewheel, I can confidently say that I do not belong on an electric skateboard. Some go 30+ mph (38+ kph)! Oh, and I agree that your rear foot's heel on the rear angled part of the widewheel is very beneficial when riding/accelerating (saw your video). For some reason, I can also turn a bit sharper when doing this.
I don't have too much experience with li-ion batteries, so I'm still learning. The question regarding the BMS discharge current was also derived from the ebay and amazon item listings where they specify the required discharge current for ebike motor wattages. I see the motor controllers are wired direct to the battery positive terminal and to the BMS C- terminal. The battery negative terminal is wired to the BMS B- terminal. I'm guessing that is how the current is limited thru the BMS.
I was planning on using two chargers for the external battery mod. Still pondering, but I believe it is still worth it because it allows you to stay at the higher voltages longer. Also, it's just nice to have the extended range in case you decide/need to take a longer ride than anticipated. An alternative mod was to machine a couple of spacers and use longer M5 screws to lower the bottom electrical cover. This could allow you to house a single larger battery.
I'm glad you posted all this info. Couldn't find too much widewheel info out there.
> Wow! Damaged columns from the rider's weight?
easy done, stand like a statue, feet together, crowd up against the pole like a classic newbie. Every time you hit the brakes you take all your weight on the pole, then when you trigger the power bend it back the other way ... rinse and repeat till pole brakes.
Add in that when you hit big bumps (think speed bumps) the front comes up and back towards you ... more stress on that pole
> The battery negative terminal is wired to the BMS B- terminal. I'm guessing that is how the current is limited thru the BMS.
to my knowledge the BMS plays no part in current limiting unless we're talking short circuit. Then it steps in to protect the pack. Do a little bit of reading on Ohms Law with two resistors in series (first being the bms with very low ohms, second being the motor).
Then recall that when the motor is spinning that there is a significant (huge) back EMF (the motor is also a generator at the same time, this was discovered by Lens in the late 1800's) which restricts the current that can flow. The BIGGEST hit of current is if you disable kick to go and then standing on the scoot like a big sack of potatoes just hit the power ... that's where big amps flow.
:-)
I'm still doing a bit of research when I can to understand the BMS. There's a generic diagram on wiki that shows a current sensor at the negative terminal which will cut discharge power from the BMS if it is operating outside of the specified paramters.
https://en.wikipedia.org/wiki/Battery_management_system#/media/File:Bms_MainController.png
I'm curious if this simply means a 15A BMS will shut off if there is a higher current load. Is this the same situation as you mentioned regarding the short circuit protection? The BMS continuous current discharge rating is not meant for limiting current as you stated, but cuts off output power from the BMS if it is exceeded for protection. Either way, it still sounds like you need a BMS with a continuous discharge current that exceeds what the load requires. You might be fine with a 14A BMS for a 15A max controller unless you disable kick and require the "big amps flow".
I wonder if this means that you could use your charge & discharge style BMS for charging only and then connect your motor controller directly to the batteries negative and positive terminals to avoid this current rating issue (will lose short circuit protection however).
Also, after dissecting my battery, I reassembled it and charged it. Now I instead of 52.5V, I am now getting 53.5V (same results as you, but without shortening wires). Not sure why unplugging the BMS improved this.
Have you seen the Rion scooters?
Hi
myself I go off the manufacturers quoted spec (not a general wikipedia entry).
as to your better voltage, did you put on a new BMS? If so thats your reason. Is it an active BMS? does it have LED's? (I assume you have read my other BMS related posts ...)
i reassembled with the original BMS because the shipping of my new BMS is delayed. i thought it was quite the coincidence that we achieved the same voltages before and after we unplugged/plugged the original BMS from the battery (52.5V & ~53.5V).
Thanks for the informative discussion. As far asI understand Widewheel and Widewheel Pro deck you can not fit more battery as the physical size is the same and almost no empty space in the deck. And 13s6p means 13 serial and 6 in parallel connection and it'll make 78 cells. In both Widewheel and Pro model the physical battery size are exactly the same. For 13.2 a 2200 ma cell and in Pro 15a battery used 2600 ma cells. So in practice if you exchange each cell with 3400 ma you'll get 20 a battery with the same size(probably a bit heavier in weigh but still they will fit). And if the original BMS supports 20a then you will have longer lasting battery(or you can get a higher a. BMS still). Theoretically and practically it will work?
Ali
correct, and you can use the comparitor here https://lygte-info.dk/review/batteries2012/Common18650comparator.php
to make an informed choice on any home build. Take a look also in my discussion here for more angles on this: http://cjeastwd.blogspot.com/2020/04/cell-obsessions.html
then when you've selected a candidate cell check prices :-)
Yeah. It's still too early for me too build my own, still learning. Maybe after one year when the battery life/performance starts to fall down. But yes it's very interesting topic. You can find for 3-4$ 3400-3500 ma Panasonic/ sanyo cells. It'll still not be so cheap but you can do it for a bit cheaper than the original battery with much higher amp capacity.20-21a. will still be 33-35% higher than Widewheel Pro's original battery which I guess it's LG cells inside.
Hi
you'll also need to factor in the price of materials associated with the build (BMS, nickle strip, spot welder, heatshrink ...)
I don't believe that the WWPro has LG cells, given that none of the others do, I'd like to see some evidence. I recall you read my post on Cell Obsessions.
https://cjeastwd.blogspot.com/2020/04/cell-obsessions.html
I opened up the deck cover under the Widewheel Pro and noticed after a month of usage there was a lot of dust inside. I cleaned it but it will get the same after some time as the cover have some holes. Other reason was to check the bolts holding the neck(they were tight-ok) from inside and also check the available space inside deck for future battery build or change.
https://photos.app.goo.gl/E9QHGFivwEAW6YEv6
That's how it looks with the 15a battery. There's a very little extra space in left right and top side. My observation is length(battery 404 mm +extra 11 mm space till the dual controller) can fit max 415 mm, width is 105 mm with mentioned little extra space and depth/height can fit 70 mm.which I think theoretically(and practically as I measured it) I can fit 18650 batteries vertically standing, and similar to your battery as you have in the pictures 5 battery can easily fit in width of deck( with using the little extra space I think even 6 will fit). This way max. 5* or 6* batteries in width and 21* batteries in length fit inside the deck. Of course we will still need some space for BMS and cables but still over 100 cells can easily fit inside. 13s 7 or 8p combination might be possible. With using 3500 mAh cells in total 24.5a(7p) or 28a(8p). What do you think about this? With such capacity battery range can be extended to 70km I think. I would even think of using 21700 cells which can have up to 5000 mAh capacity but their size is 70*210 mm but the inside deck height is max 70 mm so putting 21700 cells standing won't be possible ( maybe just to do the same structure what you have in the picture and still possible to fit 78cells in 13s*6p) and this case possible to get 30a total power. I know it's still too early for me but maybe next year I can do something.
Ali
the dust brings nothing to harm in there (for there are no moving parts) but brings you a free service: it is a superb indicator of is water getting in. Do not under any circumstances block the holes. The holes are designed to allow drying as any (haven't seen any yet) water that might get in can 1) drain out and then at a later stage 2) evaporate out.
you will note it looks pretty similar to mine:
http://cjeastwd.blogspot.com/2019/07/mercane-dual-motor-underbelly.html
Looking at your images is interesting as they seem to have addressed a similar "issue" to me with the inclusion of foam between the controller cable and the battery base: see this blog post https://cjeastwd.blogspot.com/2019/07/battery-compartment-maintenance.html
The design is good, and make sure that when you refit the base that you do not pinch any of those cables between it (the base plastic) and the body. You'll notice that the base plate has a rise that fits into a recess in the bottom of the body, doing a further (good) job of preventing / reducing water ingress along that edge.
You'll also see that the XT60 connector has small drainage recesses (shine a torch in to it or also up from below) which correspond also to weep holes.
The entire platform forms a very neat umbrella for all components.
Given that the design for the WW began as a single motor 36V system I think that its fair to say they've squeeze in a very reasonable amount of upgrades already. I keep saying to people, if you want more power, more battery or more speed - get something else.
> 13s 7 or 8p combination might be possible. With using 3500 mAh cells in total 24.5a(7p) or 28a(8p). What do you think about this? With such capacity battery range can be extended to 70km I think.
Myself I can't imagine wanting to spend over two unbroken hours standing on it, I myself do not want a "spend hours standing in one spot" transport system (that's slow), indeed standing in one spot is what the army does to soldiers for a punishment. Further all places which employ people to work who are pretty much required to stand in one spot provide a variety of systems to prevent ankle damage. So to me its a dumb idea. To me its turning the scooter into something its not. Seldom do I want to be on it for that long.
That I may want to do multiple trips in a day is so far covered by 1) its out of the box range and 2) my addition of a 4A charger (allowing me to do 2 long rides in one day).
I won't criticise or judge anyone for doing things which I'm not interested in. Each to their own.
The only worthy upgrade I've seen is that one fellow has reported that he has upgraded the pack to a 14S6P and gets that 'fresh off the charger' zip throught the ride. This requires the BMS to be exposed (as well of course a new BMS) but personally I think this is a good thing.
If I do anything to this scooter that'll be it.
:-)
Thanks for the comments. 14s sounds like it.will become 52v scooter and in practice the speed can increase.
Generally I am ok with 35 to 40 km range with one charge. And even if I have a bigger range battery I won't be using the capacity at once and standing long time on the board. I am trying to change position often during rides(as mostly in the city I have to stop often on the traffic lights and this is good time to do it). The power is more than enough for me. If something to change, it'd only be range. 3500ma 18650 and 5000ma 21700 cells has great potential. So, maybe the next year I can think of fitting more amper inside the deck. And for safety I added a small mirror which increased safety. Turning lights would also be a great safety addition but I haven't found anything suitable(better to say a suitable place to install them on Widewheel)
Cheers
Hi Ali
> and in practice the speed can increase
no it won't increase significantly (or even at all without engaging ludicrous mode), even then my steep down hill testing shows nothing significant.
> Turning lights would also be a great safety addition but I haven't found anything suitable
I have a glowing wrist band and put one arm out to signal ... I wear it on my right wrist in Australia but you'd probably wear it on your left
HINT: I find it helps to lean the scooter a bit in the opposite direction you wish to let go one hand with so that you can "pull" with the other hand to help stabilise yourself.
Practice and be aware of bumps ahead ... you'll still need to look behind you. Personally I think indicator lights are a wank on a scooter.
Hi, reading back the article and for the dualmotor there is dual controller and I understand from here each have 15a meaning in total should have a 30a BMS minimum. So in dualmotor (no matter 2019 Widewheel or Pro model) less than 30a will be problem(in peek power).
And as I see there is no correlation between BMS and battery capacity, it's more related with motor power and controller(s).
Minimum 30a BMS needed for Dualmotor for 13.2-15 even 30a battery(as battery capacity does not have affect).
In dualmotor's battery there is one input (connection for the charging port) and two output port each per one controller( all ports xt60). So here it comes the "common port or separate port" BMS.(I saw on online shops that separate port are more expensive) The BMS in Widewheel Dualmotor has separate port for charging and discharging? And the new BMS selection should be as per above info(if what I wrote is correct). And if not can you give a short explanation what're the correct criterias for Widewheel Dualmotor BMS selection.
Many thanks
the BMS needs to be able to handle the highest amps on discharge and the highest amps on recharge.
However you'll notice that they don't do much on the voltage out, except monitoring the voltage of each bundle (not highly current intensive) to turn it off if a bundle gets low, and to prevent over discharge in a short circuit state (protection).
Consequently handling higher power is easier on the discharge side. Its on the charging that the BMS does work in splitting the (say) 58V into separate channels of 4V to each bundle. I believe this is where you need to have the heat sinks.
Perhaps this circuit diagram of a 3 cell BMS will make that clearer (note almost nothing on the battery discharge side)
but yes, the max discharge current will be mentioned on the BMS
also
>The BMS in Widewheel Dualmotor has separate port for charging and discharging
yes, but then all batteries I've seen have this. If you look carefully you will see that there is an output wire and an input wire in this series of posts. Look also at your own battery
Thanks.
The maximum discharge current on Widewheel is 15a per motor, so BMS needs to have 30a level to keep it safe. And is it same with battery? cells discharge performance.Here the p level(number of parallel cells which increase the total amper) will take the stress out of battery.
Let's say comparing 13s6p-the current batteries in dualmotor- with 13s8p battery, the higher p battery potentially have higher ability of discharge amper levels? if this is true then a higher amper battery is not only extending range but bringing up the max. potential discharge
>so BMS needs to have 30a level to keep it safe
many are 60A
>And is it same with battery? cells discharge performance
look at the data.. https://lygte-info.dk/review/batteries2012/Common18650comparator.php
6P .. each cell can take 5A no problem some 20A .. 6x5 = 30 6x20 = 120
the max A comes form low speed (less than 5kmh) climbing not higher speeds.
Hi everyone,
I have a Mercane WideWheel Pro 2020 CLE with 500W dual motor since one year. I only made near 780 km with it and now i have a problem to start the scooter.
When i want to start the scooter, i turn the key and the display lcd switch off just about 1 or 2 seconds during the initialization of the scooter. The low battery level symbol flash a short time.
So i checked the charge and apparently he's ok because the red indicator in the original power outlet charger change after 5/8 secs on red to green.
I tested the output voltage of the power outlet charger and i have near 54,3 V.
I decided to open the deck of my Mercane to look about the battery. I tested the arrival voltage of the yellow connector and i have 48 V. I have the same tension in 2 output.
I'm not an expert in electricity. I'm a little lost with this problem. I wondered if the problem could be in the BMS ? I looked in the deck and i see 2 gray case next to the battery. It's the BMS ? i have 2 BMS for 2 motors ?
Somebody could help me please ? I'm lost with this problem. :(
Thank you !
Hmm ... you have a problem for sure
you need to measure the battery voltage, and your assumption "So i checked the charge and apparently he's ok because the red indicator in the original power outlet charger change after 5/8 secs on red to green." is not quite right.
however the 54.3V on the charger is a little low ... try tweaking that up a little https://cjeastwd.blogspot.com/2020/02/tweaking-up-your-charger.html
but that isn't a show stopper.
I have no idea what "arrival" voltage means, but you should remove the base plate, and check the output voltage of the pack (there is an obviously connected to the charging port end, and an obviously connected to the motor controller end. Unplug that and measure voltage across the XT-60 connector there (hint: your charger plug is an XT-60 type)
the grey cases are the motor controllers, the BMS is internal to the battery. Read my above blog post carefully again.
Thank you obakesan for your quick reply.
Since my first message i buyed a new original 230V charger for testing if my charger is allright. The second charger give the same result as my first charger : 54.3V of voltage. The color indicator make the same thing as the other charger : red indicator power outlet charger change after 5/8 secs on red to green when the charger is connected to the scooter.
So my problem isn't with the output 230V charger.
I controled the voltage battery : input and output give the same result : 48V.
I try to connect just one of two controllers and the result is the same. The scooter doesn't want to start. I try to connect only the primary controler or the second controler and 2 results are similar.
Sometimes, i look that when i turn the key start of the scooter, i have the time to look the power charge and the voltage are growing up next to 100% just before they shutting down to 0% just in somes seconds...
I'm wondering if the problem could be maybe in the display ?
Unknown
I have no idea why you bought the additional charger, I did not suggest it needed replacement. Further I think you aren't explaining the problem very well and it now seems you have a BMS issue.
Do you have a multimeter? If not get one, if yes you need to measure the power at BOTH ends (one at a time) of the battery. Yes, you'll need to dig in and measure the battery at both the charging point and the outlet end. I suspect you have a BMS issue.
I have nearly 100% confidence the problem is not in the display.
I have a multimeter and i tested all the point : input and 2 output.
My power is the same in the 3 point : 48V.
BMS problem is a problem inside the battery ?
Hi, can someone refurbish my wide wheel single 500W motor battery for me (8.8ah 48V does not hold a charge)?
Post a Comment