Golden Motor Build 48v and Beyond!

[icecube57]

A friend of mine tracked the information on the cells on my battery. Its not exactly the same cells. The tops seem different but the logo of the company and ebay vendor is uncanny.
What do you think?

http://cgi.ebay.com/LiFePO4-48v-20ah-BATTERY-FOR-ELECTRIC-SCOTTER-E-BIKE_W0QQitemZ170318686849QQihZ007QQcategoryZ11332QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
http://www.chinatoppower.com/battery/News_View.asp?NewsID=20

Model TP-LiFePO4 18650 1500mAh 3.2V
Nominal Voltage 3.2V
Battery Capacity 1500mAh
Cut-off Discharging Voltage ≥2.0V
Maximum Charging Voltage ≤4V
Maximum Charging Current 1500mAh
Maximum discharging Current 6000mAh
Charging Method CC/CV
Overall Dimensions Diameter：18±0.3mm
Height： 65±0.3mm

Weight ≤50g
Operating Temperature Charging 0℃---65℃
Discharging -20℃--65℃

If the specs are right this could discharge up to 4c with my current pack configuration thats 108A the bms is supposedly peaks up to 60A. Something is under rated or over rated. But 108A discharge is in a perfect world to.

[The Stig]

Hmmm it's probably hard to positively identify those cells in your pack...

I just got my 48V build running for a test run. Dual suspension, full size AND folding.
For me the only thing that worked perfectly was the ping battery. Other than that I had to machine the axle to fit, change hall sensors TWICE, took 3 times to get a working controller with it. All because of a bad vendor Brett... It's running beautifully now and I'm going to finish it up nice.

What rack bag are you using?

[biohazardman]

The controller is bad yes, Im getting a GM Regen Controller to replace this one RMA through the company i bought it from.

But Its the bms cutting out early on the battery because the last time i tried a full discharge it stopped at the same exact AH which was 15.5. But the controller was good on my last full discharge. When I tested the cells through the bms they were rather high at 2.7. some a little bit lower but not near the full discharge state of 2.2.The voltage was around 46 when it cut out.. The lvc on a 48v controller is normally 41 sometimes lower if you get one custom made.

The vendor says its normal that the bms is protectecting the pack. It doesnt lug or anything i still have good solid 30mph performance all the way to the 15.5AH mark and then it cuts out. But i think the lvc is set so high to prevent full discharge from damaging the cells and pack. Its well designed and i can see why the vendor sets it that way. But I ordered a 20AH pack and im getting 75% of that and verified by a volt meter that the cells arent fully discharged. Im going to charge with the BMS and discharge without it and either let the lvc of the controller kick in or manually back off when it hits 40 to 41 under load i bet i get better results.

A packs rated AH may only be reached at a very low draw. Sometimes there is even a rest period half way through the test. Makes them look good and is a practice often used. It's about getting the most from their batteries. Getting 75% of rated AH in a real world ride is not all that bad at all.

[dogman]

You're kidding right? There's runt cells in that there pack. A good lifepo4 pack will discharge at least 95% of the rated ah at a 1c discharge.

[The Stig]

I get 17AH... 18AH+ out of my 16AH ping pack when I test discharge it at 0.5C and lower!
Be the pack leader!

[icecube57]

I went out and bought a rc charger used on rc planes. Takes 11-15 DCV input. It can output 4.2, 8.4, and 12.6 volts. I used my regular charger to bulk charge it. I let it try to balance itself. I then disconnect the BMS/Balance connector. Inserted the charging pins into the appropriate connector holes for the given string i want to charge. It charges them up to 4.2v. The bulk charger doesnt let the cells get that high only up to 3.75 which is the bare minimum for charging lipo.
. Its taking a while to charge... about 1hr or more a string at 1 amp so I know they werent balanced. It shuts off and alarms when its done. I can charge at 250ma, 500ma, and 1 amp. This should help a bit with the capacity. After my repairs they were all discharging evenly voltage wise after i pulled 10AH out of them.... that was a rare sight. I knew there were runt cells when i repaired the pack but i had no way to charge them properly. And with the bulk charge it always cut off before the weak cells got full. It took several days for the voltages to come up to the rest of the pack.

[icecube57]

Speed 15-18mph. Head wind. 14.55Ah. 751wh. 52miles. 14.44 wh/per mile

[Russell]

I went out and bought a rc charger used on rc planes. Takes 11-15 DCV input. It can output 4.2, 8.4, and 12.6 volts. I used my regular charger to bulk charge it. I let it try to balance itself. I then disconnect the BMS/Balance connector. Inserted the charging pins into the appropriate connector holes for the given string i want to charge. It charges them up to 4.2v. The bulk charger doesnt let the cells get that high only up to 3.75 which is the bare minimum for charging lipo.
. Its taking a while to charge... about 1hr or more a string at 1 amp so I know they werent balanced. It shuts off and alarms when its done. I can charge at 250ma, 500ma, and 1 amp. This should help a bit with the capacity. After my repairs they were all discharging evenly voltage wise after i pulled 10AH out of them.... that was a rare sight. I knew there were runt cells when i repaired the pack but i had no way to charge them properly. And with the bulk charge it always cut off before the weak cells got full. It took several days for the voltages to come up to the rest of the pack.

I'm confused; is your battery pack LiPo (3.7 nominal/4.2 peak) or LiPoFe4 (3.2V nominal/3.65V peak)?


-R

[icecube57]

Ive discarded the charger because of that issue.It was a lipo charger but i was assured it worked on Lifepo4.It dont.

[dnmun]

ice cube, i finally got one of the golden motor controllers to work on, it was the 48V1000W with regen, pcb revision 4/08. withthe black relay in the corner for the LVC.

this is in another thread, for the controller problem, it burns up the zeners they added for the regen function problems:

viewtopic.php?f=1&t=9746

but he gave me another goldenmotor controller, for 36V with the shenzen type controller board. with the LVC resistor bridge on the outside of the board.

you can see the trace from the input battery voltage running across the edge of the pcb to the LVC bridge in this picture:

36V goldenmotor controller with the NEC 3435 40V FETs.

DSC00243.JPG (154.06 KiB) Viewed 915 times

can you take some pictures of your board and paste them on the regen controller problem thread?

you were correct that the trace you rebuilt went across the edge, but there was never anything but a trace there.

make sure the resistor on the right doesn't make contact with the trace, that resistor is the input to the first voltage regulator and is at a different voltage level.

at the time it shorted, it may have damaged the resistors to the right in the resistor bridge, which you can check with a voltmeter and a magnifying glass. possibly the op amp which takes the input from that bridge is damaged, which may account for your intermittent problems.
>>edit added, after thinking about this i doubt if it could have damaged it if the power trace shorted at that spot, since the bridge is already sitting on the battery voltage.<<

now that i got a controller to look at, i suspect we can fix yours too.

does yours have the zeners on the bottom too? would appreciate pictures over there if possible, thanks, dm

[icecube57]

I felt lazy so I rode the Silver Comet trail WOT from mile marker 4.2 to 14.2 and back. Here is a 17minute video until my camera died. I was doing 27-33 mph most of the time.
WOT 95% of the time. Only pedaled on acceleration. It was wet.
Terrain mostly flat.
Total trip was 20 Miles.
Starting Voltage was 60.17.
Ending Voltage was 51.24.
Lowest Voltage under load was 47.50.
I consumed 716wh from my pack. (48v 20AH)
I peaked at 34.14A and 1906 watts.
Consumed 14.4AH total.
0.72 AH a mile
35.8 WH a mile

[icecube57]

Yesterday i had an Near Death Expereience. I just rode 40 miles on the trail to get a little exercises. I was on my last 2 mile stretch. I was crossing a bridge at 30mph and I heard a ping ping ping ping. Then i thought....something was rattling my entire ride. I slammed on the brakes and double back. Im looking around like wtf was that. I found my C lock washer.... The one that fills in the little dip in the fork drop outs for an even fit. I look down. The nut was barely hanging on. Im like omg. Then I was like the other one is still on there . I checked it with my hand and it spun right off. I nearly fainted. I had my tool bag with me and took my channel locks and put the washer back in place and tighten the wheel back down. I admit... I got a little bit lazy with the safety check. Bike has been problem free for 3 months. I thought they were on there tight. This goes to show you can be cocky about your how nice your build it. I think it was only the grace of god... or the weight of myself that kep that wheel on. It was so loose that the wheel wobbled and if i would have picked it up the bike motor would have fell out. Even though the nuts were loose the torque arm was tight. I think thats what kept it on to be honest.

[The Stig]

No substitute for "propper engineering."

My advice to you: THREAD LOCKER + LOTS OF TORQUE on those axle nuts...

[icecube57]

So i bought another bike. My previous bike had a slew of problems. Rear wheel had bad bearings. Changed wheel out. New wheel kept breaking spokes. The crank is getting loose. Ive adjusted it twice. Brakes have always been lack luster. The suspension made noise while riding and hitting bumps.

The bike I bought was a Mongoose "Snare" from Walmart. I picked it up for 229 plus tax. It has front and rear disc. It is a 24 speed. Geared pretty low from the looks of it. The front chain ring is bigger that my old build and the lowest sproket in the rear is pretty small. Ill post more details on it late. I got my bike 75% complete. I ran the wires. Mounted the wheel. The front fork is THICK!!!!! My nuts arent mounting flush with the drop out like they should. Im going to take the file to it and file it down but the drop outs have to be 6-8mm of solid steel. I removed the front disk to fit the motor. I have to go get some studs to mount v-brakes on front. The rear disc brake works like a champ. I can stop on a dime now. I still have to mount my controller. The Watts up meter isnt going on the handle bars but sideways on the main tube. Its out of the way and all I have to do is flip it up. I find that i only actually use it for AH reading since i know how my bike runs now under most conditions. I know I can ride 25-30 miles without pedaling. It gives me useful information but none that i need in my face at all times.

[philf]

Yesterday i had an Near Death Expereience.

Maybe not as close a call as that squirrel that crosses your path about three minutes into your video

[icecube57]

I think i posted a topic on kamakazie animals. One actually did get caught in my spokes. He died. I took his lifeless body and gave him a respectful toss in the woods. The flies followed me for days... if i stopped more than a minute... they were on my fork like rat on a cheeto. Birds like me to. I have about 2-3 vidoes of near misses while riding.

[icecube57]

Just finished my transition to my new bike. I did some grinding on the drop outs... they had the quick release lip so i dremeled it down even and went back with a file to even it out... even after grinding its still thick as hell. I got everything assembled. I bought a handle bar riser stem to give me 2-3 inches of additional handle bar height. The stock handle bar height was unadjustable. It is so freaking comfortable. New front shimano v brakes grab and stop on a dime. Rear disk brake....168mm Pro max disc.... leaves some to be desired. They work good for slowing but it seems like abnormal force is required for them to really stop. But when both brakes are used together you really feel it and would stop very quickly in an emergency... may even throw me off the bike...The suspension is wonderful I dont feel any bumps with this fork. The rear suspension is really stiff... not in a bad way... it dampens but it doesnt have the unecessary softness like my previous bike did. Ive never rode an 24 speed bike. This 11tooth sprocket in the rear kicks ass i can pedal with the motor well into the high 20s and still feels like average pedaling. Im really satisfied with this bike. It shifts very smooth and accurate.I only wish the handlebars werent so thick. I cant put my lights on and other stuff on my handle bars. I did a test ride on my low battery pack... it seems to be faster even with my 75% discharged pack i was still hitting 30mph easy. I will do more tests tommorrow with a fresh pack. I think it may be 2-3 mph faster.

[Hyena]

You may have mentioned it earlier, but what current does your 1000w motor draw when cruising at top speed on the flat? My 500w GM only draws around 10a which is really good, but I'm tempted to upgrade to a 1000w to chase the extra speed. It'd probably also switch to a rear wheel so I can upgrade my front forks and have more options (than heavy solid steel ones)

[icecube57]

Its weird. Im in the 15-20 A when in the high 20s and after 30 it falls off dramatically to 10-15 or less especially on a slight down hill. But you need the extra amps to get to the tops speed of this motor. Its also rider dependent. Im 280lbs.

[icecube57]

Im getting some new goodies. Im going go 60 and then 72v.

I have a 48v 20AH LifePo4 pack with 16.5AH usable.

I plan to add 4 12v 4200mah pack to create a 14-16AH 12v pack to put in series with my LifePo4 pack. It should be 74 off the charger and settle down to 66 once the float charge is gone.

At 72v It should be 88 off the charger and settle to 79 after float charge is gone.



I bought 4 12v 4200mah NIMH battery packs from All-Battery. 16$ a pack plus 4$ shipping per pack. The packs are rated for 10c or 40A. I plan to parallel 4 in series with my Lifepo4 pack to get 60-66v 16H and parallel 2 and series 2 in series with my Lifepo4 pack to get 79-88v.

I bought 2 2.3A Chargers.

I bought what i believe is an Analog 36-72v 35A Crystalyte Controller with CA plug. for 96$ Lightly Used.

I bought a Direct Plug In CA. to monitor my packs since they will sit above 60v which my Watts Up cant read.

I will still use my Watts Up meter to monitor the discharge on my NIMH pack to verify their capacity and to monitor voltage during discharge. What is the save discharge voltage for 12v NIMH pack. What should the charge voltage sit at.

All of these upgrades should ship in later this week or weekend... perhaps late as monday or tuesday of next week.

[docnjoj]

Hey IC57! Nimh should not drop below 1 volt per cell. Nominal voltage is 1.2V. Fully charged around 1.44V. Use the correct type charger that monitors Dt and Dv. (Change in temp and the "knee" in the voltage curve for shut off!)
otherDoc

[icecube57]

I bought some prius packs. I bought 6. Im going to use them to make a 3s2p 21.6v nominal 25.2v charged at 13AH. Might even use the at 6s 3p for 43.2v at 6.5AH. I have those 12v 4200AH Tenergy NIMH Cells on the way also. I was doing research on my chargers.... If they cant detect DELTA voltage it shuts off after 8 hours. I was wondering should i charge at 1A or the 2.3 A. If it misses delta V I hate for it to over charge but it will cut off if its not detected. Im trying to get 3 more if the price is righI so i can have a solid 72v 15AH pack

[docnjoj]

I think IC57 that it would be good to read Powermeds posts on those Prius packs. I vaguely remember he said stuff that makes me think they don't charge like our "normal" NiMh cells! Just a thought.
otherDoc

[icecube57]

I read it and from what i remember it just misses delta V and he used cc / cv and charged up to 8.3v untill current dropped and then charged 15 min after that. I think im going to slow charge at 1A so it will take 6.5H hours to charge and if it misses the Delta V it will cut off 1-2 hours later. So I cant overcharge by much. The seller told me to worry about compression during charging but charging at low currents.. as long as you keep an eye out for heat voltage and bloating i should be able to charge safely.

[icecube57]

I finally hit the beyond. I got pissed sitting waiting for my controller to be shipped. I kinda successfully moded my 48 shenzhen to go to 72v. I replace the input caps with 100v 1000uf caps and I replaced the on on the fet buss with a 160 2xxuf cap. I had to replace the input resistor and then add more when i had power up problems. I think the voltage was to high on the regulators. I still think they are too high. A 33-34 v on 48v lifeo4. I cant seem to set my CA shut its reading to high. I have it set pretty close when its reading below 10A. At speed im getting 40A when it should be 28-29A I had my watts up and tried to make adjustments on the fly but it gets close but no cigar. I rode around my neighborhood at 66v resting 61-62 under load. I was using my 48v and a a 12v 12AH nimh booster pack. Little top heavy with that booster pack.... i really need a new bag. The streets were a little wet and i had traction issues. I was trying go up the hill in my neighborhood. My front tire was slipping. It had way more torque that at 48v alone. Once it leveled off it takes off pretty quick into the 30s. I almost lost control a few times way faster than i been on a bike. I topped out about 36 unassisted I have no straight areas where i stay. I will do more tests later if my controller feels up to it. If my CA speedo is set right. Free wheel speed is exactly 50mph. It was reading the same thing as my schwinn speedo. I had to do the CA pole and wheel size reduction to get it to read correly i think i have it set at 14 pole a 1246 wheel size. I tapped the yellow hall wire.