bochka
1 mW
..
HATE MY BATTERY!!
- Thread starter bochka
- Start date
biohazardman
100 kW
Low C-rate batteries, duct tape packs and Headways, must have a large footprint to supply the amperage you can get with higher C-rate batts such as the a123 and Turnigy units you mentioned. Nothing wrong with that if you want a large AH battery so you can get down the road some miles. Else you can use the smaller footprint and weight of the high C-rate batts such as the a123 and looks like the Turnigy. Sounds like you have one or more dud cells in your pack. Don't feel bad about the first pack I bought some inexpensive ones as well. Once I learned my lesson I never went back though. Looks like the Turnigy would be easiest to build with although these
http://endless-sphere.com/forums/viewtopic.php?f=31&t=36589
would work as well if you don't mind tearing them apart and building your own. Probly need 3P unless you beef up the tabs. Headways would not be hard to build either. Might even find what you are after in the for sale section of the forum.
Me I like the a123s myself.
http://endless-sphere.com/forums/viewtopic.php?f=31&t=36589
would work as well if you don't mind tearing them apart and building your own. Probly need 3P unless you beef up the tabs. Headways would not be hard to build either. Might even find what you are after in the for sale section of the forum.
Me I like the a123s myself.
John in CR
100 TW
Bochka,
Interesting proposition about the HobbyKing LiFePo4 batteries. I didn't know they offered 30c LiFe prismatic packs. I wonder what the expected cycle life is on those. I'd look at the Zippy's instead of the Nanotechs though. It looks like they have a significant weight advantage, and once you remove the excess wiring and packaging to DIY your pack you should end up well above 100wh/kg.
You're looking at a lot more cost and weight, but the increased safety factor, since you're parking at work should be worth it. Hopefully the real world cycle life makes it economically on par with the smaller and lighter, but inherently higher fire risk RC lipo packs.
I'm still kicking myself for passing on a 2004 Stinky with that huge triangle back in '08. If you run out of triangle room for the size pack you want, don't be afraid to put part of the pack out in front of the headset. The 74V10ah I have there on my SuperV is only noticeable when I pick up the front by the bars to flip the bike around in a tight space, but that's nothing compared to the back that has a 45lb hubbie with rim and wheel clamped in the rear dropouts along with another 74V10ah inside the extended swingarm in front of the tire. At 65mph WOT it simply can't be beaten as a street commuter.
If you change your mind on the Stinky, let me know. I'll buy it from you. :lol:
John
Interesting proposition about the HobbyKing LiFePo4 batteries. I didn't know they offered 30c LiFe prismatic packs. I wonder what the expected cycle life is on those. I'd look at the Zippy's instead of the Nanotechs though. It looks like they have a significant weight advantage, and once you remove the excess wiring and packaging to DIY your pack you should end up well above 100wh/kg.
You're looking at a lot more cost and weight, but the increased safety factor, since you're parking at work should be worth it. Hopefully the real world cycle life makes it economically on par with the smaller and lighter, but inherently higher fire risk RC lipo packs.
I'm still kicking myself for passing on a 2004 Stinky with that huge triangle back in '08. If you run out of triangle room for the size pack you want, don't be afraid to put part of the pack out in front of the headset. The 74V10ah I have there on my SuperV is only noticeable when I pick up the front by the bars to flip the bike around in a tight space, but that's nothing compared to the back that has a 45lb hubbie with rim and wheel clamped in the rear dropouts along with another 74V10ah inside the extended swingarm in front of the tire. At 65mph WOT it simply can't be beaten as a street commuter.
If you change your mind on the Stinky, let me know. I'll buy it from you. :lol:
John
e-beach
10 MW
bochka said:
If you want to do it on the cheap, check out my thread here:
http://endless-sphere.com/forums/viewtopic.php?f=3&t=39690
I suggest that you get as much in the frame as possible then the rest on the rack. As you have found out weight on the rack is bad. I cracked a rib in a bike crash in January of this year due to my pack on the rack.
I never go fatter then 4 inches on the battery frame because my legs rub. It will take some soldering and 10 gauge wire to get your batteries in the frame and the remainder on your rack, but you can do it if you really want to.
Get the very high strand count wire from RC suppliers because it is very flexible. Then use your imagination.
Hope this helps!!!
bochka
1 mW
I am looking at this bike and the thought of putting 32 headway cells in the frame seems like a daunting task. These cells are big! I am leaning towards A123 at this point
but still looking around to see other peoples set up.
how do I fix these dud cells? I just opened my BMS and this thing looks fried up! sent a message to the seller about this but in the mean time what should I do? I was thinking about charging the cells directly and monitor the whole pack closely with my turnigy watt meter....what do you guys think?
but still looking around to see other peoples set up.
I had a scott bike with a rack and my battery broke the rack after about 2 months of constantly hitting bumps and pot holes! so no more rack for me
Haha I doubt I will ever sell this bike....it rides amazing..first time I sat on it i fell in love! hopefully you find an old stinky you can restore.
how do I fix these dud cells? I just opened my BMS and this thing looks fried up! sent a message to the seller about this but in the mean time what should I do? I was thinking about charging the cells directly and monitor the whole pack closely with my turnigy watt meter....what do you guys think?
dnmun
1 PW
fried up? do you mean that the pcb under the shunt resistors has discolored from the constant heating from the shunt resistors? on the top cell in the picture?
wesnewell
100 GW
I think he's talking about all the resistors that have popped in the first row. Just need to find out why they popped and replace them.
dogman dan
1 PW
Sounds like you want performance no V power battrery will provide. Nor a ping either.
See if Cellman at Emissions Free can make you an A123 pouch cell pack. Then you'll be free to do the controller upgrades you will be craving soon.
See if Cellman at Emissions Free can make you an A123 pouch cell pack. Then you'll be free to do the controller upgrades you will be craving soon.
bochka
1 mW
dogman said:
I went on http://www.emissions-free.com/ and sent them an email to see if they can make a 52v 24AH or 48v 20AH triangle battery for my frame.
My frame is pretty big so i think a triangle pack will fit in perfectly...still waiting on their response
dnmun
1 PW
so you have the 3 headways in series, 3S2P and the two pings in series with that so it is 19S20Ah wide?
how do you keep the headways from getting loose where they screw onto the lug in between you use for the balance lead? there is a torque spec from headway on how much you can tighten the screw.
you know that the screw cannot go deeper than 6mm into the negative terminal on those i hope. if you go deeper then the screw tears a hole in the bottom of the casing and ruptures the cell. very bad.
how do you keep the headways from getting loose where they screw onto the lug in between you use for the balance lead? there is a torque spec from headway on how much you can tighten the screw.
you know that the screw cannot go deeper than 6mm into the negative terminal on those i hope. if you go deeper then the screw tears a hole in the bottom of the casing and ruptures the cell. very bad.
skeetab5780
1 MW
Sorry you hate your battery, i had a vpower 48v10ah for my first pack and it worked great..i got around 1000miles and decided to sell it before it totally died
on a side note, the bike with the motor on the front forks? did u lose your front brakes when doing this mod?
on a side note, the bike with the motor on the front forks? did u lose your front brakes when doing this mod?
arkmundi
10 MW
No questions should remain about the superiority of A123 nanophosphate LiFePO4 cells - they own the license to MIT research and patents. There are various formats. I'd suggest 26650 format for your situation, since you'd be able to mold a shape that works. Problem is getting a hold of those. Lot's of folks buy Dewalt packs and deconstruct them. I'd contact Cellman and see what he says about availabiltiy, as he'd know. LOVE MY BATTERYbochka said:
skeetab5780 said:
This was just my initial mounting to test the motor position. Afterwards I reinstalled the vbrake boss mounts that came with the forks when I bought them 10 years ago. They are stratos mx6's with disc or vbrake option. I couldnt do this on the rear as my frame has no vbrake option.
If people are worrying about vpower batteries after 1000 miles something cant be good with them as lifepo4 is expected to last around ten years I thought.
I have only ever emptied my ping pack once (started hitting 2.7v under load 2.95v resting) and my cellpro powerlab 8 charger reported 20.5ah's had soaked back in while on charge back to 3.55v a cell. Thats after 2 years and between 2000/3000 miles.
skeetab5780
1 MW
nice atleast you have front brakes again...
no im in no way worried i beat the crap out of that pack and ran it at twice its C rating.. it put up a fight but the bms doesnt balance for crap
no im in no way worried i beat the crap out of that pack and ran it at twice its C rating.. it put up a fight but the bms doesnt balance for crap
Dave Sloan
100 W
- Joined
- Jun 22, 2009
- Messages
- 128
I have two 48v 20ah VPower batteries. One is five years old and the other four. The BMS on one blew last spring. It was my fault for not having a precharge resistor. I got a new different BMS from Cellman and it works great. To top up a charge with a three amp charger - wait until the red light turns on then plug in a 100 watt 120v light bulb into the output that normally goes to the controller - this will drain the battery untill it restarts the charger. Wait about five minutes for the charger to bring the charge to 61v at which point it will turn off and the green light will come on. Immediately unplug the light bulb. I have done over 1000 miles on both batteries and they have lost very little capacity = I did a 38 mile trip today at 17 miles per hour and had 50.4 volts - I can do 25 miles per hour but only get 30 miles at this rate before the battery shuts down.
bochka
1 mW
I have been in touch with Cellman and he is pretty busy working on customer orders for the next 3-4 weeks. He advised me to consider using Samsung NCM cells because they are lighter and cheaper than a 20ah A123 pack. I have to measure myarkmund said:No questions should remain about the superiority of A123 nanophosphate LiFePO4 cells - they own the license to MIT research and patents. There are various formats. I'd suggest 26650 format for your situation, since you'd be able to mold a shape that works. Problem is getting a hold of those. Lot's of folks buy Dewalt packs and deconstruct them. I'd contact Cellman and see what he says about availabiltiy, as he'd know. LOVE MY BATTERY
frame space and send it to him so he can see how many cells will fit in the pack he will make for me
I was just riding home on my regular pedal bike from work and I was saying to myself..if i'm gonna get a custom pack might as well get the best kind of battery out..so i might just spend $$$$ on a custom A123 pack instead of the Samsung NCM pack he recommends...hmm
bionicdan said:
Exactly! the cells are no name cells!...I opened my vpower pack up and I counted like 5 spot welds that were broken or out of place causing my pack to perform poorly...couple of the cells are dead so I just took aprt the whole pack
and might use the good cells for a future project or sell them to whoever is interested....
Ultimately I want performance, ped-ability, and even weight distribution on my bike...
