2WD Semi-Recumbent Recycled-Parts Cargo eBike: "CrazyBike2"

[amberwolf]

I found the camera card, put away next to Tiny's meds in the doggie meds/etc cabinet in the kitchen. :? Pics at end of post.

Due to higher wh/mile usage (30-35) probably cuz of the trailer, I didn't get the mileage I'd hoped, so I had to recharge the pack some yesterday and today to be sure I'd be able to get to/from work, as it got down to the saggy / less-responsive level on my way home from work on Sunday night.

Oriignally I was to have yesterday off, and had thought the pack might make it all the way thru Monday....but between teh higher usage and work changing my schedule again, moving my day off farther down the week again, it didn't work that way. Theoretically I have tomorrow off, assuming it doens't get changed again, so if I can get enough sleep to trust myself to open up the pack and check things, I'll have a chance to do that.

 

[amberwolf]

About 9 hours of ragged sleep later, after Tiny dragged me out of bed for her breakfast around 10am (with YOgi still snoring beside me), I am awake enough that I got th ebike on the "stand" of pails and started to do the discharge tests, by rubber-banding the thumb throttles to WOT, which uses almost 4.8A or so for unloaded WOT on both wheels at the same time.

The lighting pack test was also started with the battery medic on it, and it's nearly balanced, except the next-to-top cell which is several hundredths below the others.



But it also shakes the bike badly from resonance between the two wheels' unbalanced spots, so I had to slow the front wheel down some (it's the worst due to larger diameter I guess), making the unloaded WOT current only about 3.8A.

THen I remembered I needed to pull the pack out of the frame to open the ammocan to get to the balance wires.... **sigh**

Turned off the bike, and after much effort, including haivng to loosen the front derailer and remove the chainring crank, becuase I'm so uncoordinated I can't lift and twist and pull the pack out around it, or on the left side either :? , I got the pack out and opened up.

At this point the dogs were pretty bored, as it took a while to get that off there.




Checked balance with the Maxpro 6-cell checker, but it only reads 5 cells no matter what I hook it up to. Dunno what's wrong with it but it's probably the first or second cell, because when I check the top two cells on their own balance tap it only shows one of them. Despite not showing all the cells, the ones it does show are all well-balanced, at 3.59 or 3.60V, some flickering between the two.
View attachment 6



View attachment 4

I verified with a multimeter that the balance leads are all ok from cells to contacts.

I pulled the Battery Medic off the lighting pack it's monitoring during that discharge (using the headlight at a little more than 4A), and it does read all the cells via the balance connectors, also at 3.59-3.60V for every cell. The first image actually captured a flicker between 3.59/3.60 for the 3rd cell down.





THat's all at no-load. Then I had brunch while typing most of this. Was taking forever to upload images though now it's going ok (started typing it up almost 2.5 hours ago, but keep getting up to see to the dogs and check on the bike, wash clothes, do other chores I haven't been able to do for the last week+).


The lighting pack test finished, though I forgot to put the wattmeter on it so dunno what Ah/Wh capacity it has. Guess I'll find out when I recharge it.

I checked in on ti just in time, when the low cells (top two) got down to a hair under 3V under load (2.8V and 2.9V), with the other two at 3V and 3.1V. Turned off the headlight and they sprang up a couple of tenths each.

Hooked up my little Sorenson at max current (~250mA) at 3.3V, and am now individually charging each cell, starting with the lowest. WHen they are all equal there, I will hook up the Accucell6 and do the usual 5A max charging to 16.4V, which is 4.1V/cell.






Now it's running a discharge test on the traction pack, and under load from both wheels and all lighting (including brake and a turn signal flashing), about 4.8A average, all cells are still balanced, down to 3.48V as I sat down to add this to the post, except the cell just below the most positive one is 0.01/0.02V (flickers) below the rest.

At this point it's about 11.5Ah or so, cumulative between charges and discharges and regen and this test, since I last charged the pack fully more than a few days ago. But we'll get another reasonably accurate reading of capacity when I recharge it, since it takes very little more to charge than is actually absorbed, and can be called the same for practical purposes.




Now to go check on it again and do some yard stuff now that it's warm and sunny out there.

 

[amberwolf]

In the post above I said around 250mA charge rate for the little sorenson, I meant 750mA, though it's down to around 380mA now, at 2.98V.

The bike discharge test had to be stopped, as that second-down-from-top cell suddenly dropped to 1.8V from ~3.2V, while the rest stayed at that level within 3 hundredths of each other under the load.

So that cell has potentially a lot less capacity than the others, might even have been damaged further by that deep discharge when I was hauling the stuff home last week (or was that the week before?).

As I have "spares" because I'm not using it as an 18s pack, only 14s, I swapped out the cell 13 and marked the new as 13A with today's date, and also marked the original 13 with today's date and why.

13A is at storage voltage, so I am in process of draining it down to match the rest of the cells before I try restarting the discharge test.

I forgot to note down the CA's Ah used on the pack before I shut it off so quickly, as cell 13 was so low I didn't want to drag it to nothing. Have to note it when I start the test again, but that will probably be a few hours while 13A drains down (bunch of paralleled aluminum-cased power resistors, as I don't have anything else handy that really works for a single-cell load ATM).



The lighting pack is almost balanced and ready to bulk charge again.

 

[amberwolf]

Taking lots longer than I'd hoped to drain that cell, even when I parallelled 18 of the power resistors...which turned out to be 150ohms each, not hte 15 I'd thought I'd read on them. So 8 ohms at 3.7ish volts is only 0.4A or so, plus about the same from the headlight at this voltage, and as it's a 20Ah cell that started nearly full.... That's theoretically at least several hours, maybe half a day, before I get it down as far as the others.

I looked around but don't have anything else that is low enough resistance to do much, other than stuff that amounts to a dead short.

I thought I might try paralleling various motors, but they make nearly zero difference to the drain, except the ones that end up a dead short, windings get really hot, and that's just not happy.

I did jsut now think about one other option: The luxtrol dimmer. It's meant to handle up to 1000W of lighting, so it ought to be able to do this, assuming I don't have to turn it down to dead short to get a decent load out of it. :lol:

Now to go try that.

In the meantime, the lighting pack is charging up now.

 

[amberwolf]

spare cell 13A finally reached 3.29V, median of what the others were at, so I put it in there, tightened everything down, and restarted discharge test.

It was at 14.1Ah at that point, and I could hear the motor slowing down some as I reached 14.6Ah as cell 14 and 3 dropped down to 2.85V (3 measured on BM plugged into cells 1-6, and 14 measured on one of two multimeters I had monitoring 13A and 14. Maxpro started working on all 6 cells when I wiggled it around enough (something in it's PCB I think) so it was on 7-12).

The rest were anywhere from 3.00 thru 3.04V, cell 13A at 3.11V. I switched off the bike and cells slowly rose back up a bit more than a tenth of a volt from there, except 13A that rose to 3.20V and 14 that rose to 3.11V. So everything ended up close to 3.1-3.2V after resting about 5 minutes.


I turned on the lighting but not motors, and that tenth V went away, but it all stayed steady at that lower voltage for as long as I had the patience to wait, maybe 5 minutes or so. Probably could've gotten more capacity out of it from there, if I'd waited, but unless it can drive the motors at that level it's unimportant for my purposes.


Now it is recharging thru the CA (which I reset trip stats first to see what hte recharge Ah is), so we'll see what the recharged capacity turns out to be. My guess is around 15Ah, give or take half an Ah, based on the previous results. Not as much as I'd like, but good enough for most of my purposes, and at least I'll "know" what my range is with this pack for now.

Previously it had been a guesstimate, and I'd actually been figuring I think around 17-18Ah usable but the pack has aged more than I thought, probably for a few reasons.

One of the first is that it ends up parked in the hot sun a lot of the time, and there's not much to do about that here. Maybe if I ever finish the new "fairing" coverings over the frame it'll shade it a little from direct sun at least. I did have coverings over it for much of the summer, and all of the spring and winter, but this pack wasn't inside the fairings--the RC LiPo ammocan pack was. This pack was strapped to the rightside cargo rails then--though now it is n the middle of the framework in front of/under the seat.


Another thing is my charging it fully every time, because I may need it's full range/capacity at any time, though usually I don't. When I do need it, I may not have time to top off the charge, so I just keep it full most of the time. That ages cells, too.


There was another factor but I forgot what I was going to type about it...too tired I guess.


I had something else other than that, but it's gone away, too. Maybe I'll remember later. :/

 

[amberwolf]

More deep sleep...interrupted but better than usual, missed even the alarm at end of Accucel charging, which is pretty raucous.

Charging finished up sometime a few hours ago, about as I expected for capacity. 15.3Ah for the traction pack, and 14.55Ah for the lighting pack (which I didn't drain back down from the re-balanced level).

Neither pack is as balanced as it was before, but I will fix that later. Gotta get ready for work right now--it took quite a while to get teh pack back together and reinstalled in the bike, but I managed to do it without destroying antyhing, I think.

I did go ahead and extend the balance leads out the main cable hole,though, so I don't have to do this again just to check them or balance them.

 

[amberwolf]

Nothing fell apart on the commute, so I guess I put it back togehter alright.

No noticeable difference in performance via the data on the CA, though my imagination said it "felt" better, like it accelerated harder. :lol:

I"m sure that is all from the fact I'd been riding it at less than full charge for days before that, and there is a very defiinite difference in how hard it pulls when full vs medium to empty.

Butt dynos lie.



Anyway, next step is to check out the A123 EM3EV / Cellman pack for balance, which means actually opening up the shrinkwrap to access the balance wires, I think. That pack isn't normally on the bike,but I use it for extra range sometimes. I'd like to know if it's balanced, and if not to fix it, and also to load test it for capacity so I know what range to expect from it.


The RC LiPo pack, also used for extra range sometimes, I already know is deteriorating, since the cells are puffed, though I don't know how badly that's affected it's range. At some point I need to go thru it as well, and verify it's capacity under load, too.


Given my present work schedule I dunno how long it'll take me to get around to these things, but if I put them in the thread there's a chance I'll be reminded of them when I do have a moment here and there. Since they're not on the bike I also don't generally have to worry about having them operational at any particular moment, so I can poke at htem as time permits.

 

[amberwolf]

few days on and it's down around 8Ah, about 16 miles. (forgot exatc nubmers).

just under 27wh/mile, normal commmute riding.

battery seems ok, is only a little less than half full right now. will see how it deosw later when close o t emtpy, for sagging and such.

it does seem like it sags less, but it's just an impressino i can't verify with data, as i woud need an under-load graph at various soc before and after cell replacement.

keep meanin gto to chekc balance but forget every time i'm up.

new problem on the bike though, is when i use the right-turn signal, the whole lighting system flickers really really fast, so somethin is shortin out the wiring for that signal, probalby to the frame. i'll have to troulbeshoot it before work tomorrw cuz i couldn't hodl the meter leads tonite, have tried several times and am just too tired to o do it. cant sleep yet either though.

 

[amberwolf]

went back to fix the lighting problem but it wasn't a prpblem anymore, and jiggling wires around c an't recreate it.

ca shows 9.3ah used, 17.4miles ridden, 26.9wh/mile

all ells are 3.68v +/- .01v

good to go for work in a few minutes i uess.

now if only i was.

 

[amberwolf]

~11Ah and 22 miles. should be ok for today's commute, then a final rundown tomorrow on my day off this week, riding around the block by the house or something.

gonna see if i have any other jst extension cables to stick the cell monitors up on the bars so i can see which sag worst during acceleration. another thing i meant to do ages and ages ago.

 

[amberwolf]

30 miles and 14.8Ah before it turned gutless on acceleration, sagging down to 41V and only getting around 1300W for max power (less than half of normal peak power).

I couldnt' see all the cells at the same time doing this, but using the battery medic to watch 6 at a time I could see them in groups during the test. I forgot to note which cell, but one sagged down to 2.8V during that kind of load, while the others were around 3.1V, and a couple others nearer 3.0V.


So I'm gonna go ahead and call it's practical capacity 14Ah for now, and I'll have the "extra" 0.8Ah as an emergency buffer, I suppose.

Practical certain range I'll call 25 miles, then.


Oh, and wh/mile ended up right at 26.9, with light winds the last couple days.

The wh/mile dropped as the pack voltage dropped, presumably because it couldn't supply quite as much power during the hard startups, which is where most of my extra power gets used on commutes, vs the longer rides with fewer starts from a stop vs the distance, where I get lower wh/mile.



Anyway, there is definite capacity loss since I started using this pack but I can't find my original data posts in this thread about it right now, and all the original paper notes are long gone in the fire and aftermath.



Now I've gotta check out the A123 pack's balance and whatnot. Probably not today...see the housefire thread for the other stuff.

 

[amberwolf]

charging put in 15.1Ah on traction pack. All cells show within 0.02V of each other.


dunno charge on lighting pack, becuase several times during charge it alarmed with "connection break" on the accucell, and when it does that you can't get back to the data screen, so no way of knowing what it had already charged up to/etc. But it didnt' start out run down all that much, so it doesn't really matter too much.

 

[amberwolf]

guess lighting pack had more discharge than i thought, cuz the last segment put in 8.9Ah. previous segments were anywhere from a tenth as long to half as long, and i would guesstimate that in total they were almost as long as this segment, so i was pretty close to the max capacity of the pack used up. not sure how, though, cuz i diddn't think i used that much power each day. maybe i need to put the wattmeter on it to see how much gets used nowadays with the headlight. on my commute.



i did get a chance to check the balance of the a123 pack, though, and it's about perfect, within 0.01v on every cell, presently at 3.33/3.34v / cell.

all i had to do to get to the bms balance connector was to pull the pack halves out fo the ammocan, then cut away the end-wrapped part of the shrinkwrap, leaving the actual shrunk-tight part intact around that half (the other half's wrap was removed by the original owner so it might fit it's intended destination better).

Then I just slit teh tape holding the palstic cover over the bms balance wire plug, and pulled that plug out of the bms to plug into the extension off of the battery medic.

no other testing yet, but would like to test for capacity, cell sag under load, etc. i think i may strap the pack to the bike and use it for my commute for the next week, with the main pack as backup.

one catch isthat just like the main nmc pack id' have to take it off the bike, open up the ammocan to check balance and sag/etc....worse actually cuz i also have to disconnect hte bms balance plug, as i don't presently have a y-cable to use for that. i knwo i have some but not where they are. well, i know i used ot have some but i guess i might not anymore. no idea where they might be if i do stil have them.

i don't remember if it's fully charged or not... i think i charged it up in anticipation of the original cancelled ride with wayne early this year, but i can't remember. guess i should put it on it's charger to be sure.




pics below.

 

[amberwolf]

post about energy cost to charge the bike, moved from here:
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=66877&p=1006672#p1006672

first, keep in mind math isn't my best skill, so if i make a mistake in how to calculate things below, please point it out.

fwiw, my eig nmc 14s 20ah pack takes about 15.1ah, about 770wh per the ca, to recharge 14.8ah, 748wh used.

that doesn't include charger efficiency, but lets pretend it's 70%. that means about 1.42x the charged power to actually do the charging. that's 1.42 x 770wh = 1093wh.


the actual rate isn't shown on my bill, but:

most recent bill used average of 5kwh / day for $1.09 / day, so let's say $1.09 / 5kwh = $0.218 / kwh


but in my case almost all of my cost is not in the electricity, but in the service charges:

monthly service charge $17.00
onpeak energy use $3.44
offpeak energy use $7.68
city tax $0.76
county/state tax $1.77
total $30.65

so only $11.12 of power cost
and $19.53 of service charges and taxes.

So in reality, that's gotta be factored in, meaning service / power is 1.756x as much for service charges vs power.

then that times the power cost of about $0.218/kwh makes a real cost of $0.383/kwh.

Since it takes about 1.093kwh to recharge the pack, that means if i recharge from dead (rare) it costs about $0.419 to fully charge it.

Mostly I use about 1/6 of that on each commute, or less.

so that's about $0.07 a day for energy cost, or around 1.75 a month.

For me, because I use so little power for anything, it's actually a significant part of my total electric bill--this past month it would be almost 6% of my total energy costs.





Doesnt' include battery cost, etc.

 

[BLUESTREAK]

HI AGAIN AMBERWOLF,I HAVEN'T BEEN ABEL TO UPLOAD PICTURE ,IT SAYS IT'S TOO BIG. I WILL TRY AGAIN LATER ON, BYE. COOPER.

 

[amberwolf]

if you use windows there's at32resizer.exe, free just google that name. set it to target width 600 and maintain aspect ratio from width and leave everything else like it is, and then it'll resize any jpg file so it fits on es.

 

[BLUESTREAK]

going to try again. HI AMBER, I finally did it this is my 2nd photo ever on the internet. i will post more photos soon. COOPER. :lol: :wink:

 

[docnjoj]

That is some nice looking woodwork, Bluestreak. Does that trike have a cover for the rider?
otherDoc

 

[BLUESTREAK]

Thanks doc, no I don't have a cover down here in tampa I only ride in nice sunshine weather. BTW seems like I remember you having the tech. infomation on the (NUVINCI 171 ELECTRIC SHIFT MODLE) if you do I need to talk to you about that. THANKS COOPER.

 

[docnjoj]

Thanks doc, no I don't have a cover down here in tampa I only ride in nice sunshine weather. BTW seems like I remember you having the tech. infomation on the (NUVINCI 171 ELECTRIC SHIFT MODLE) if you do I need to talk to you about that. THANKS COOPER.

Not me, Bluestreak. I wouldn't touch Nuvinci with a ten foot pole. Too much loss and could break easily. I am using the 2 speed motor, and just had to rebuild it.
otherDoc

 

[amberwolf]

There's a thread with NuVinci in the title that has all the tech info I know of.

And yeah, that is a nice trike.

I can't imagine any of mine will ever look nice.

 

[BLUESTREAK]

This is my best trike.

 

[amberwolf]

You sure there's enough spokes in them rear wheels?



It'd be fun to drill some more holes in a hubmotor flange and use it with one of those rims, wouldn't it?

 

[BLUESTREAK]

MAYBE I could add some more, I think I have a better photo if I can add it.

 

[BLUESTREAK]

onemore AMBER.thanks for letting me practice here.