Ebike "The Resurrection"

[doc007]

I don't know if what you're planning would work with balancer...but I really think you should make 5 of 4s2p then series them after...I have not had experience to explain why it should be this way but I do know we had quite big discussion on this couple years back.

it would be a bit of a pain if your balancing your pack every charge, but with bulk charging it works a treat, and you can always balance with a bm. afterall, after paralleling the packs via the balance leads, you've done the exact smae thing as paralleling them via the discharge leads.

I plan on Bulk Charging 90% of the time. Like so:

The remaining 10% will be either one of the two forms of balancing: (a) traditional method of using a balance charger to charge the pack via the main leads and then letting cells at optimum voltage discharge via the balance leads until the lagging cell reaches optimum voltage -OR- (b) using Ykicks method of finding a lagging cell and hooking into it directly via the balance lead to bring it up to optimum voltage [http://endless-sphere.com/forums/viewtopic.php?f=6&t=41331&start=30#p655336]

 

[doc007]

The modified bullets (http://endless-sphere.com/forums/viewtopic.php?f=6&t=41331&start=30#p663931) will help support making parallel connections. In this case, I will also need to cut the original bullets in half.

Charging: The 20s2p pack will have to be broken into 4s10p to balance charge but that will only need to be done 10 out of 90 times. The remainder of the time, the pack will stay as is and be bulk charged. In fact, I could balance the pack in the 20s2p configuration if I used 5 battery medics (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10328).

Casing: As for the pack itself, I plan on making a saddle type bag for it. It will not stay on the bike. Something along these lines: http://image.dhgate.com/albu_206103583_00/1.0x0.jpg

 

[doc007]

Also for balancing, your setup is pretty ideal for a tench like system.

Tench's set-up is awesome! I think I mentioned earlier about making a wooden block like this. His design and drawings definitely helps put everything into perspective. Thanks for the link!

Maybe I will wire up the balance leads to a serial port or a molex connector if I decide to balance via a balance charger instead of battery medics.

 

[doc007]

New toy :

 

[doc007]

Just ordered one of these too:

Hyperion EOS 1420i Net3 Charger - 1S-14S, 20A Max, 550W

 

[doc007]

More supplies (crimp sleeves):

Crimped up a connection based on previous idea (http://i47.tinypic.com/14kh0ci.png) I had for a connector that will parallel and series at the same time using a minimal amount of wire and space :

Sleeved:

And shrinked:

Connected:

Another connector in the making:

 

[doc007]

Previous wiring diagram with hypothesized connectors:

Completed wiring connectors. Crimped and sleeved :

 

[doc007]

Ok, so I guess I'm going to need a precharge resistor to prevent the sparks from flying.


I found this website to help calculate it:
http://scriptasylum.com/rc_speed/nospark.html

Just wondering what these two values should be (I'm running a Greentime controller, 15fet 4410 50A):

....as for updates:
- Throttle is mounted!
- Controller mounted!
- Dead cell in battery discovered! I didnt even get to use that battery once!!!! The voltage for this pack was fine when it came in, but after a year of no use one cell dropped to 0.1.
- Motor phase and hall combo figured out!

Thanks fellow ES member, iovakind, for helping troubleshoot the issues!! Of course, out of all the wiring combinations we tried for the halls the one that worked was the last on the list!! Ridiculous!!

 

[sn0wchyld]

Ok, so I guess I'm going to need a precharge resistor to prevent the sparks from flying.


I found this website to help calculate it:
http://scriptasylum.com/rc_speed/nospark.html

Just wondering what these two values should be (I'm running a Greentime controller, 15fet 4410 50A):

....as for updates:
- Throttle is mounted!
- Controller mounted!
- Dead cell in battery discovered! I didnt even get to use that battery once!!!! The volts we fine when it came in, but after a year of no use one cell dropped to 0.1.
- Motor phase and hall combo figured out!

Thanks fellow ES member, iovakind, for helping troubleshoot the issues!!
Of course, the combination of wires that worked was the last on the list!! Ridiculous!!

just use something around the 150ohm mark, 3-5w, should be plenty. The fact that you're using a separate connector is enough on its own really... it will corrode but since its not going to carry much of the current while in use, it doesn't matter much. Though your input caps will appreciate the lack of start-up current (less likely to fail).

 

[doc007]

just use something around the 150ohm mark, 3-5w, should be plenty. The fact that you're using a separate connector is enough on its own really... it will corrode but since its not going to carry much of the current while in use, it doesn't matter much. Though your input caps will appreciate the lack of start-up current (less likely to fail).

Ok, cool the plan was also to save the controller

How did you calculate that I would need 150ohm 3-5 W? Also, how long would it take to reach the desired voltage?

I'm thinking of buying these: http://www.radioshack.com/product/index.jsp?productId=2062316

Paralleling all five should give me 150ohm at 2.5W. Is that right? ...

 

[sn0wchyld]

just use something around the 150ohm mark, 3-5w, should be plenty. The fact that you're using a separate connector is enough on its own really... it will corrode but since its not going to carry much of the current while in use, it doesn't matter much. Though your input caps will appreciate the lack of start-up current (less likely to fail).

Ok, cool the plan was also to save the controller

How did you calculate that I would need 150ohm 3-5 W? Also, how long would it take to reach the desired voltage?

I'm thinking of buying these: http://www.radioshack.com/product/index.jsp?productId=2062316

Paralleling all five should give me 150ohm at 2.5W. Is that right? ...

nope... paralleling resistors reduces the net resistance. the equation is as follows
R1*R2/(R1+R2) = new R
in this case, r1 and r2 are both 150 ohms. then you need to do it again for each subsequent resistor your putting in parallel, with R1 as the result from your previous calculation (new R). so you'd have
150*150/(300) = 75
75*150/225 = 38
38*150/183 = 31
again for #4
and again = your paralleled resistance. probably around 25 ohms or so - a bit too low. The resistors may carry enough current to blow them too, though they could survive since it will be very brief.
If you want to use 1/2 watt resistors, its probably easier to use say 5 30 ohm resistors in series. this will give you 5 x 30 =150 ohms, and 2.5 watts. otherwise you could try 5 x 1200ish ohms in parallel, which should come out somewhere near 150 ohms. You should be able to find some 2 watt resistors at radioshack too, just use 2 x 300-400ohm in parallel or 2 x 75-100 ohm in series. any combo that equals about 150-200 ohms and ~3 watts will be fine.

Technically, the charge time to 100% is infinity - but realistically charge time to a reasonable % (about 90-95%) would be around 3-4 seconds @ 150ohms, off the top of my head. I could be wrong though, if you connect and still see a spark, then you need to wait a bit longer next time. A handful of sparky connections early on wont do any harm anyway - atleast not enough to ever notice - and they'll be far smaller than with no recharge connection too. you could also put a small ~12v light globe in series with the resistors, when the light goes out your ok to connect - thought it may not last many cycles. Mainly dont stress about the exact #'s too much. If you use anything between 100-500 ohms, at about 2-5w you should be fine.


http://www.radioshack.com/product/i...&filterName=Type&filterValue=2-watt+resistors 2 in series would be good.
http://www.radioshack.com/product/i...&filterName=Type&filterValue=2-watt+resistors 2-4 in parallel. Way more wattage than you need at 4 but just giving another example. 4 would be around 250ohms.

edited for some clarity

 

[doc007]

That clears it up perfectly, thanks! I don't think Ive used that equation in ~12yrs.

Anyone have any suggestions on a good source for a small amount of resistors at a reasonable price?

 

[sn0wchyld]

ebay and DX.

 

[doc007]

Any ideas on what this white wire is for?

Also, if anyone is curious the combinations for the phase and the halls to a Greentime controller is as follows:

Phases:
(Controller --> Motor)
Blue --> Blue
Yel --> Yel
Gr --> Gr

Halls:
(Controller --> Motor)
Red --> Red
Blk --> Blk
Blue --> Yel
Yel --> Gr
Gr --> Blue

 

[doc007]

So I pulled a USB cable from old mouse to salvage the connector and wire for the halls:

Need to throw some solder on this and wrap it up into a drip loop (note: mysterious white wire :? coming from the hub is terminated with small piece of electrical tape):

This side of the connector will go to the controller (need to desolder the connector from the mouse):

 

[doc007]

Ok so here it is soldered up to the halls coming out the hub:

All cleaned up with drip loop and all:

Controller side is another story. This is quite possibly the worst solder job ever. Dont know if its the crappy iron from Harbor freight or the fact that I didn't have flux :? Either way I'm going to try to clean this up tomorrow. Too bad I dont have my hot glue gun. I could have used it to reinforce the plug for disconnecting. Here is the solder job (you've been warned... ):

 

[Ykick]

Not good my friend. Flux (or lack of) isn't the issue you just need more practice IMO. Maybe some proper size heat shrink too? I've never used Hot glue for wiring jobs.

FWIW - I've gone to crimping 2qty Futaba servo connectors for my axle/controller Hall wires. red/black power wires in one and the B/Y/G signal wires in another. They fit through the axle nut/washer hardware and make it much easier to remove wheel and/or swap controllers.

 

[doc007]

I'll have to look into those connectors. Crimping is great. I crimped my bullets. Super easy and clean. No mess & no fumes!

I noticed that my solder tip isnt tinning. I tried to give it a coat with solder but it wont stick. I noticed that the small part of solder that did decide to stick works very well in transferring the heat and solder to my work however, the part of the tip that somehow got tinned is the thicker portion of the tip. Basically im finding it very difficult to control the solder flow with the thick section of the tip. (Ill try to post a pic of the tip when i get to my computer)

Any thoughts on how to get it tinned up?

 

[Ykick]

I'll have to look into those connectors. Crimping is great. I crimped my bullets. Super easy and clean. No mess & no fumes!

I noticed that my solder tip isnt tinning. I tried to give it a coat with solder but it wont stick. I noticed that the small part of solder that did decide to stick works very well in tranfering the heat and solder to my work however, the part of the tip that somehow got tinned is the thicker portion of the tip. Basically im finding it very diffult to contTrol the solder flow with the thick section of the tip. (Ill try ti post a pic of the tip when i get to my computer)

Any thoughts on how to get it tinned up?

Charcoal tip will never solder right. You can try filing the bad spot into fresh metal and re-tin with solder. Might work for a while or not at all but at this point you have little to lose?

You shouldn't leave non temp regulated soldering iron sit around hot for long periods of time.

 

[doc007]

Great thanks for the "tip" I will try it out. Let you know how it goes!

I guess I should have read the reviews for the soldering iron:

By Ice King
Comments about Chicago Electric Welding Systems 30 Watt Lightweight Soldering Iron:

After i got some good Made in the USA plated tips for it, it works fine. Throw the tip out that comes with the iron (`cause it's JUNK) and get some good tips in 1/8'' diameter.


By fatty
Comments about Chicago Electric Welding Systems 30 Watt Lightweight Soldering Iron:

Low quality tip doesn't take tinning well, corrodes in heater element. Poor quality metal bends and distorts almost immediately.

 

[doc007]

Charcoal tip will never solder right. You can try filing the bad spot into fresh metal and re-tin with solder. Might work for a while or not at all but at this point you have little to lose?

That's right, nothing to lose, everything to gain! Ahhhh soo much better:

Before:

After:

 

[doc007]

Also got a chance to clean up this mess:

Wrapped each lead with electrical-tape, then wrapped all the leads together in electrical-tape and shrink tubed over it. Much more sturdy and less likely to short out. It would have been nice to squirt some hot glue in there for more structural support but I cant find my heat gun. Overall, I think it came out OK:

 

[doc007]

Update:
Needed to figure out a way to run my Hyperion EOS 1420i Net3 Charger (1S-14S, 20A Max, 550W). I was considering running it using my bulk charger but the voltage is too high. So I decided to modify some server Dell server PSU's: model# DPS-500CB A REV 05

I was going to try to isolate the ground by changing out the screws and such but I found a better way. All I needed to do was cut some jumper wires at position J920 and J921 to isolate the case so I can run two of these PSU's in series for 24V.

Here is the UNmodded PSU showing an open circuit reading on the multi bc its not touching anything:

Here is the UNmodded PSU. This time showing a closed circuit reading on the multi when touching the case:

Here is the MODded PSU showing an open circuit reading on the MM when touching the case (success!!) :

Here are the two jumpers (J920 and J921) I needed to cut to isolate it:

Here is the pin config that I need to solder (bending the pins so they touch did not work well at all):

 

[doc007]

I must say, with the soldering tip issue fixed it is working fairly well after filing it down to expose some new metal. I've been doing a lot of soldering lately and the tip has been holding its tinned coat.

Finally got the PSU's fully modded and running at 24.8v. Here are some pics of the mods:

Wired up the pins to trick the PSU to turn on:

Snipped and heat shrunk to keep it isolated from the other pins:

Then it was off to the main terminals. Tried to figure out the best method of getting the job done. In the end I bent the two leads inward to hold the bullet terminal or wire in place as I put some solder on it for reinforcement:

Up and running at 24.8V :

Not done yet! So in order to run the new software I had to upgrade to firmware ver 5.86. This was a pain in the butt. For no explicable reason, it would not work! I tried several combo's of on and off and plugging and unplugging. Nothing worked! Finally, I gave up and posted on ES for some help. Gave it one more shot before calling it a night and then off she went. Taking the firmware like a champ lol. (oh here is the tread for anyone else who might have a problem upgrading the firmware (https://endless-sphere.com/forums/viewtopic.php?f=2&t=51755)

Here was firmware injection attempt 1 of 2,000,000,000 . I snapped a pic thinking that she cooperated on the first shot. In reality it got stuck at 18%. By the time I got it, I wasnt even thinking about pics :

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Anyone have any suggestions on what I should do when charging my battery pack for the first time? I'm thinking cycle once and charge to 95%. What do you think? Should I cycle it more or dont even bother. I'm not sure how long it would take to cycle on the charger but I figure this would be the safest bet. The packs are brand new but they were bought last year.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

[doc007]

Update: Went through each cell. One by one, the old school way, with a multi-meter I checked all the cell voltages. My HobbyKing order for a cell checker is taking forever!! Can't wait till it's in. Checking Lipo cells with it will be much faster.

I also figured I should start logging the cells to see if any problems arise over time. Here is the spreadsheet I made in Excel to help keep track of everything (notice Cell #3 of pack # 8 is not doing well). Should I be storing this pack in a safety container?!

Here's that excel spreadsheet:

I also made a list of stuff I should consider when charging and discharging these packs:

Minimum Capacity: 5000mAh
Configuration: 4S1P / 14.8v / 4Cell
Constant Discharge: 20C
Peak Discharge (20sec): 30C
Max Charge Rate: 5c
Pack Weight: 528g
Pack Size: 139 x 45 x 44mm
Charge Plug: JST-XH
Discharge plug: 4mm Bullet-connector

I figure the following would be the best discharge and charging values when using the balance charger. Is this what you would recommend? or is this too conservative?