Motorino XPn Chinese ebike (scooter)

[mistercrash]

Cost is not the issue, it's just that I want to be sure I get the correct stuff. Anyway, after looking it over again, I figured some of the things I would need. Here's a link to Albert's schematic http://www.avdweb.nl/Article_files/Tech-tips/Spot-welder/Spot-welder-controller-circuit.jpg

A couple small PCBs
One 15 ohm 50W resistor with aluminum shell
One 390 ohm resistor
One 220 ohm resistor
Two 330 ohm resistor
One 100 ohm 1W resistor
One 100nf 400V capacitor
Two BT151-800R Thyristors with two heat sinks
One MOC3023 optoisolator triac driver 6 pin
One four pole screw terminal block

I found all of it on ebay.


Not sure what a BDC switch is, it's installed on the Arduino http://www.avdweb.nl/Article_files/Tech-tips/Spot-welder/Timer.JPG

Not sure which switch to get for the ''weld current switch''.

 

[Laserman]

Bcd switch it looks like a multi position switch
For the weld switch you want a momentary normally open contact switch
I would check on the c33 capacitor as it looks strange to me the value that is I have heard of micro farad or uf but not nf which would be nano farad
Check in any docs that are with the schematic

Jim

Nope error here in brain you just want an toggle type switch
For the weld control

 

[mistercrash]

That capacitor can be found easily by searching for ''100nF 400V''

http://www.ebay.com/itm/WIMA-Polyes...868?pt=LH_DefaultDomain_0&hash=item19c957a99c

That multi switch would be something like this?

From what I understand from the schematics, it is a 5 pin top adjust switch?

I ordered a small piece of square aluminum rod and some copper square rod to make the electrodes and electrode holders. Once the electrodes are in place and functional, I will try to weld with just the switch I have now. If the results are satisfactory, I'm not sure I would bother to make it just like Albert's welder.

 

[Laserman]

Yup peers looks good

 

[mistercrash]

The spot welder is done now, in the pic it is fixed to a scrap piece of plywood, I had to have a solid base to calibrate the tension on the electrodes. The electrodes are made of pure C101 copper and the holders are made from a 0.75'' square 6061 aluminum rod. I made it so the 2 gauge welding cable touches the electrodes inside the holders. It looks nice...... But it doesn't work, I hear the ''humm'' when it's on, I read a voltage of 2.9 volts at the electrodes, but when I set the electrodes on the end of a cell, nothing happens but the ''humm''.

EDIT: Many if not all of the MOT welders I saw on the web used 220V transformers. Mine is 110V. Could this be the problem?

EDIT II: after closer inspection, the problem seemed to be a matter of getting both electrodes exactly at the same level so they both make good contact with the surface of the cell. I got a weld but not a pretty one, one of the electrodes made a big spark, it must have been making contact but not at the same pressure as the other one.

 

[MitchJi]

Hi,

Motorino is now offering a LiFePO4 48V 26 Ah battery for this scooter including the charger for over $1200. Expensive and would defeat the purposehttp://endless-sphere.com/forums/viewtopic.php?f=14&t=52162 of why I got this thing in the first place, the major reason being to save money. Thanks for responding and your suggestions are noted, your info might get me to upgrade later on for a better price. If I do, I'll just have to watch my speed

$1200?!!

Eight of these would give you 57.6V nominal and 60AH, for about $800.
http://endless-sphere.com/forums/viewtopic.php?f=14&t=52162

 

[mistercrash]

Hi,

Motorino is now offering a LiFePO4 48V 26 Ah battery for this scooter including the charger for over $1200. Expensive and would defeat the purposehttp://endless-sphere.com/forums/viewtopic.php?f=14&t=52162 of why I got this thing in the first place, the major reason being to save money. Thanks for responding and your suggestions are noted, your info might get me to upgrade later on for a better price. If I do, I'll just have to watch my speed

$1200?!!

Eight of these would give you 57.6V nominal and 60AH, for about $800.
http://endless-sphere.com/forums/viewtopic.php?f=14&t=52162

I can't remember when I posted what you quoted but I know at that time the Leaf batteries were not available. I agreed that the $1200 battery was way too expensive, I never really considered buying it for long. I built my own 74V 30Ah battery out of Sony 18650 cells from DoctorBass. Cost me around $700 all inclusive. The Leaf cells are really cool but if I get a working battery spot welder going, I would go with 18650 cells again. If I had the money, I would go for brand new US18650VTC5 cells and build a 74V 52Ah battery. You still have that Zenn for sale? I wish I could know how it performs in Canadian winters, the thing was manufactured here in Canada and couldn't be driven in Canada. Political horse puckee.
https://www.youtube.com/watch?v=Ri2BG2qOvCg

 

[mistercrash]

I need to make a new battery soon for my scooter, I took a ride today and once the CA showed the 18S20P battery had given 10.5Ah, there was not enough power to make the scooter move. Fortunately I was close to my house so I pushed it back home. 26 km was the maximum I could get riding at a governed speed of 34 km/h. The consumption was 26.2Wh/Km, not bad for a 220 pound scooter and 260 pound rider.

20 cells in parallel should give 30Ah. But it's a soldered battery so some capacity was lost assembling it, and the battery was boiled shall I say up to over 70 degrees Celsius when I experimented with automotive battery warmers. So I'm not surprised.

 

[mistercrash]

I have the last 20 Makita packs coming from DoctorBass. Once those cells are sorted, I should have the 400 I need to make the new battery. I presently had 248 cells I had all sorted and just sitting to see if any would drop in voltage. They sat for a couple months and today, I checked the voltage on all of them. I found 9 more cells I had to trash, either they was an internal short in them or they were down below 2V. So I'm left with 239 good cells. I hope I get the total of 400 cells I need from the last 20 packs coming to me.

I received the nickel strips from A123RC. It looks like very good stuff, pure nickel, not nickel plated. 7mm wide by 0.2mm thick. I tried to weld some small pieces to cells and this is good material to work with.

 

[LockH]

Interesting! Notice how almost NObuddy on Alt-Planet ES gets involved in this long-running thread? Why d'you think that is?

(Sorry about stating to some watt might be obvious. Sorry!)

EDIT: Sorry! The tech is wonderful... but in electric terms, propelling a relatively large, "heavy" (?) vehicle from zero RPM might seem very "20th-century"?

 

[John in CR]

I received the nickel strips from A123RC. It looks like very good stuff, pure nickel, not nickel plated. 7mm wide by 0.2mm thick. I tried to weld some small pieces to cells and this is good material to work with.

I can't think of any need for additional nickel tabbing. I've processed thousands of Makita cells and never purchased any. The key is using what comes with the used packs. Keeping the good cells in their factory arrangement, and removing the bad cells carefully in a manner that leaves as much tab as possible with the good cells, then you have plenty of tab to make simple solder connections of tab-on-tab to form your strings. If you want to parallel at the cell level, then that is easily done with fairly small gauge wire and a soldering iron. Of course at the ends the parallel connections need to be more substantive, but that's simple too.

Hopefully your approach isn't to remove the factory tabbing from all cells, or otherwise reduce them to 1 or 2p by 1s. Doing so not only increases your work by at least 10X, but you also lose the cell matching inherently in place. ie If a used pack is perfectly balanced, then the factory tab weld connections of the good cells is proven AND that good block of cells is well matched.

 

[mistercrash]

Interesting! Notice how almost NObuddy on Alt-Planet ES gets involved in this long-running thread? Why d'you think that is?

I don't know man, why don't you explain it to me.

 

[mistercrash]

John I know that you don't approve of separating all the cells, but as I said just above, 9 cells showed good voltage just out of the pack a couple months ago and today they were down below 2V or at 0V. How could I weed out those 9 cells if they are left connected in parallel with other cells. Maybe LockH can explain it to me or maybe I'm just thick and the result is I work too hard making a battery.

EDIT: John I just thought of something, how long has it been since you worked with Makita packs? I can tell you that with the new packs, it is pretty difficult to only get one or two bad cells off of a pack.

 

[Laserman]

Crash, have you tried to use your battery welder to de weld the junctions if that works it might save you some time

 

[mistercrash]

I've been practicing on a few cells to get a good rhythm going with the switch on my welder. The best and fastest way I found is to just leave the flat piece of nickel tab that is welded on the cells by the manufacturer and weld the new nickel strips on top of it. While practicing, I've been getting consistently good and strong welds by doing it that way.

 

[mistercrash]

I took my old CBA II and tested 4 random Makita tool pack cells from the bunch I have to make a new battery. With my scooter, the average load I put on a 20S20P battery made with those cells is 25 amps just puttering around town at 34 km/h. 20P of 1.5Ah cells should be 30Ah so I thought a load of 1.3 amps on a single cell should be pretty much the equivalent of a load of 25 amps on a 30Ah 20P string of cells. Close enough anyway. I did the tests at 23 degrees ambient from fully charged down to 3V. The weakest of the 4 cells gave me 1.395Ah and the strongest 1.495Ah. So now I know that I safely have 1.3Ah per cell to work with, at 20P that's 26Ah.

That's all a poor man like me can get

 

[mistercrash]

I've been looking around for these and found them at SuPower-Battery on ebay.

I changed a couple things on my welder to make it work better. The two arms with the electrodes are isolated from each other, I also isolated their movement so that they can adjust better to the top of the cells. I did follow Albert's method of measuring how much amps I get out of this welder and I'm a bit baffled by the result. So here's the formula he used: I = U * diameter [mm2] / (0.0175 * length [m]). So here's my result: 0.28 X 49 / (0.0175 X 0.38) = 2063 amps?????

On another note, I sat down in my shop with a beer and some music and started removing the tabs on each cell. I got pretty fast at it prying them off with a utility knife and cleaning up what's left with a diamond disk on the Dremel. I did 100 cells in two and a half hours. 300 more cells to go
In case someone palms their forehead reading this, lets do some math. I got these cells for $1.42 each shipped. The same cells brand new might cost something like $3.20 each shipped. 400 times $1.42 is $568. 400 times $3.20 is $1280. The difference is $712. It should take me 10 hours to clean all the cells of their metal strips so I'm getting paid $71.20/hour to do it. :lol: The metal tabs of Makita tool packs is real cheap nickel plated stuff.

 

[mistercrash]

I have over 400 Sony US18650V and VT all cleaned up, sorted through and ready to equalize before welding them into a battery. The last 20 Makita packs I got from DoctorBass were all of the new kind which are welded differently than before and have these plastic halves that totally surround the cells. I thought I'd share how I got these packs disassembled and the cells cleaned up in the fastest way I could think of.
First thing to get is a long T10 temper proof TORX bit. I got a complete set on ebay for $30.

Once the cells are out and the BMS is off, you get this.

I used a tungsten carbide bit on the Dremel to grind at the weld points. I used just the tip of the bit to make dimples at the weld points, not going too deep to not damage the cells.

Once the weld points are grinded it looks like this. The more you make, the faster you get. By the third pack I was flying through these things.

With a small pair of pliers, it was just a matter of yanking off the nickel tabs off of the pack. then you get this and the plastic holder can be separated once you take the two TORX screws off. Keep the silicon protectors so that you can reuse them.

Then I use a diamond disk on the Dremel to clean up any residue of nickel tab left on the cells. This disk is much less abrasive than the tungsten carbide bit and takes away the minimum of material needed to clean up the cells.

Now I have to build something simple to parallel 400 cells together to equalize them.

 

[John in CR]

I have over 400 Sony US18650V and VT all cleaned up, sorted through and ready to equalize before welding them into a battery.

They were already welded and in nice convenient perfectly matched blocks with proven tab welds. Cutting them into individual cells results in 10X the work and higher failure risk.

 

[zEEz]

They were already welded and in nice convenient perfectly matched blocks with proven tab welds. Cutting them into individual cells results in 10X the work and higher failure risk.

Exactly: unless this is needed to eliminate some bad cells from within packs, I see no good use of much of the required time to dismount everything first: not doing that, you could end up being payied something around 300$/hour

have fun, nevertheless :wink:

 

[inedible]

unless this is needed to eliminate some bad cells from within packs,

Having read the whole thread, that seems like that's the case. These are all "dead" makita battery packs, and in my experience a "dead" lithium pack will usually only have one cell that's actually dead.

 

[mistercrash]

Sometimes it's the BMS that fails and the cells are good. Sometimes, the BMS failed and took a couple cells with it. So look at that pack again and please explain to me how can you take just one or two cells out of it. :lol: It can't be done without taking all of the tabs off. I'll say it again, I can't afford brand new loose cells, but with loose cells, I can make which ever shape of battery I need. I don't want to play with blocks.

 

[Laserman]

Nice step showing the process I like what you are doing, I wish I had the funds to get a lithium pack set for my xpn, maybe I will win the lottery some day hehe ( fat chance ) but hey all u need is one ticket and if I did well there would be a hell of a party and a few big orders going out

 

[Laserman]

Did you get all your cells out and equalized yet? Hope fully it's all done and your just waiting for your cells to level out and show which are bad and which are good just hope it's most of them are good and you can make a 72 v pack hehe or 2 x 48 and really extend your drive ing range

 

[mistercrash]

I've been busy doing other stuff. All my cells are sorted out, I did it days ago and I equalized them with a parallel box I made which can contain 400 cells. They're sitting in a cardboard box until I get the parts I need to finish repairing the scooter.

I thought I stayed on top of the fight against rust but I missed the bottom bearing of the steering column. The thing was totally seizing in rust. Plus the right front shock was leaking oil on the brake caliper.