48v 25ah LiFePo4 !!! Finally !
- Thread starter Ypedal
- Start date
xyster
10 MW
Sad...pathetic...impatient...immature.... :? I've done that too :wink:Ypedal said:
GGoodrum
1 MW
Yipes, that is one motha of a pack there. 
If are worried about preventing an over-discharge condition, you could add this nifty new circuit Bob Mcree just came up with: Click Here. What it does is monitor the vol.tage on each cell and if any one gets below 2.7V, it triggers the brake inhibit line on the controller. Pretty clever, actually. I'm going to be making up a bunch of a123 sub packs, and i plan on adding
Anyway, looking forward to hearing more about this new pack, congrats.
-- Gary
If are worried about preventing an over-discharge condition, you could add this nifty new circuit Bob Mcree just came up with: Click Here. What it does is monitor the vol.tage on each cell and if any one gets below 2.7V, it triggers the brake inhibit line on the controller. Pretty clever, actually. I'm going to be making up a bunch of a123 sub packs, and i plan on adding
Anyway, looking forward to hearing more about this new pack, congrats.
-- Gary
Ypedal said:
merry christmas!
early xmas around here for a couple of people.
although the other battery pack that i think storm got from sam @ yesa looks to be like rectangular square shape i like to know the difference in cells he did say you could order cells by themselves i should try to get a picture off of him .
efreak
Ypedal
100 TW
Ypedal
100 TW
I weighed the pack
48v 25ah = 24.4 lbs
For the fun of it i put one of my Odyssey 12v PC925's on the scale ( 25ah SLA ) = 24.4 lbs exactly !!!! how ironic ! That makes the LiFe pack 75 % lighter than SLA, but able to deliver more wh.. !! wow.
The pack started unloaded at 56v and dropped to 49.1v under 4 amp load, 6 ah later it's still at 49.1v !!!! talk about flat discharge curve !!!!!
48v 25ah = 24.4 lbs
For the fun of it i put one of my Odyssey 12v PC925's on the scale ( 25ah SLA ) = 24.4 lbs exactly !!!! how ironic !
That makes the LiFe pack 75 % lighter than SLA, but able to deliver more wh.. !! wow.The pack started unloaded at 56v and dropped to 49.1v under 4 amp load, 6 ah later it's still at 49.1v !!!! talk about flat discharge curve !!!!!
Attachments
recumbent
100 kW
Ypedal said:
8) Amazing how they weighed the exact same as the 12V SLA, noteworthy indeed
I gotta get myself some of those for next summer.
Thanks for the showing us the data. 8)
Ypedal
100 TW
12ah .. 48.7v 8)
Lenk42602
10 kW
ypedal,
how is the pack holding up?
how is the pack holding up?
Ypedal
100 TW
Don't yet know. 
The chargers endedup not lasting very long, one blows fuses, and the other one is buggered up as the LED's don't show correct charge status etc..
So i'm waiting on 16 single cell chargers from Tony at http://www.voltphreaks.com . I"m going to need to charge this pack with a pigtail and single cell units until i receive replacement chargers from FalconEV i'm told sometime in November.
The chargers endedup not lasting very long, one blows fuses, and the other one is buggered up as the LED's don't show correct charge status etc..
So i'm waiting on 16 single cell chargers from Tony at http://www.voltphreaks.com . I"m going to need to charge this pack with a pigtail and single cell units until i receive replacement chargers from FalconEV i'm told sometime in November.
Lenk42602
10 kW
I have been talking with Dave from electric rider.com regarding his eonyx 48volt battery with bms. I am waiting for him to complete testing and case work before he makes them available for the general public.
His 36V packs are in stock, and so far he is very happy with their performance.
I am waiting to get the dimensions for his 48v pack - 36v dimensions are going to be too wide for my V 2.0 center mount frame design, so i figure the 48v will be even larger. Hopefully I will be able to unpack the cells and reconfigure to be no wider than about 5 inches or so.
What are the dimensions of just one of those cells on your pack?
This lithium stuff seems to be still in the development phase.
If i can't easily maneuver the eonyx batt, I am thinking of just sticking with lead or nimh or nicads, pump em up to 72v and wait until the lith technology (including chargers for the packs) is a little more fail safe.....
Thanks,
Len
His 36V packs are in stock, and so far he is very happy with their performance.
I am waiting to get the dimensions for his 48v pack - 36v dimensions are going to be too wide for my V 2.0 center mount frame design, so i figure the 48v will be even larger. Hopefully I will be able to unpack the cells and reconfigure to be no wider than about 5 inches or so.
What are the dimensions of just one of those cells on your pack?
This lithium stuff seems to be still in the development phase.
If i can't easily maneuver the eonyx batt, I am thinking of just sticking with lead or nimh or nicads, pump em up to 72v and wait until the lith technology (including chargers for the packs) is a little more fail safe.....
Thanks,
Len
Ypedal
100 TW
If you go nimh/nicad.. i suggest NIcad over nimh. Self-discharge is not as bad and harder to kill them. just slightly larger in size for the same capacity/weight.
recumbent
100 kW
Lenk42602 said:
It certainly seems that way with many chargers and bms circuits shorting out.I think the batteries are secure & good by themselves, it's just the cheap chargers and bms circuits ruining the batteries reputation.
i've put on around 1500 miles on my milwaukee electric v28 batteries. i got 4 in november 2006, 2 more in march 2007 and 2 more in may 2007. I've been rotating to try to even out the usage on all 8 (i use 6 at a time). I'd say these Li-Mn batteries have proven themselves. The bms has worked well. The chargers have worked well.
xyster
10 MW
Likewise, I have over 2,100 miles on my self-assembled pack of 300 lithium laptop cells. This pack, and its 20 single-cell chargers, have proven itself to me, and there's no weak-link BMS to worry about.
TylerDurden
100 GW
Like Jon, my stock Rigid Tool 24V emoli packs are doing fine. They get me to Home Depot and they power my tools when I get back.
The 1/2" hammer-drill is heavy, but has enough torque to require two hands.
The 1/2" hammer-drill is heavy, but has enough torque to require two hands.
Lenk42602
10 kW
Those a123 dewalt packs seem like the way to go - I am just not yet comfortable enough with my own skills to wire 8 of those packs together and not destroy them......
I have read a bit so far about the subject here, but actually seeing and watching the process would instill so much more confidence.....
I have read a bit so far about the subject here, but actually seeing and watching the process would instill so much more confidence.....
everyone talks about a123 being the better battery but for e-bike applications-- especially for controllers at 20 amps, i have to say milwaukee is the better battery simply because it holds more energy. 4 dewalt packs are said to be good for 8 miles. 4 milwaukee packs are good for about 12 miles and each pack holds fewer cells (7 for milwaukee vs. 10 for dewalt).
TylerDurden
100 GW
4 24V Ridgid packs are good for 12mi... but at 12mph on my heavy ghetto-cruzer.
If you are thinking dewalt the new Gary post dimistifies the process. I can tell you that post the other day gave me the confidence that I could do this without unneccessary mods. if I decide to go that route (Thanks G)
They only thing is getting a hold of the the small connectors that are used for balancing wires. rubberied shrink wrap man it looks great to boot!!!
but personally i could wait for laifebatts they are to be a bit easier to assemble I am sure.
efreak
They only thing is getting a hold of the the small connectors that are used for balancing wires. rubberied shrink wrap man it looks great to boot!!!
but personally i could wait for laifebatts they are to be a bit easier to assemble I am sure.
efreak
CGameProgrammer
10 kW
I've caused many shorts when assembling my A123 packs, and the cells always remained perfectly fine. The BMS gets destroyed if it's connected when a short occurs, but the cells are good.
This is likely due to the fact that they can handle so much current that the wires or tools I'm working with act as a fuse, since they vaporize and cut the circuit.
This is likely due to the fact that they can handle so much current that the wires or tools I'm working with act as a fuse, since they vaporize and cut the circuit.
xyster
10 MW
CGameProgrammer said:
Yes, very comforting to know the loss of your ring finger will prevent the destruction of your battery.
GGoodrum
1 MW
xyster said:Yes, very comforting to know the loss of your ring finger will prevent the destruction of your battery.
Well, my finger healed, but I still have the arc-weld pits on the ring.
Ypedal
100 TW
OK.. long time since i've updated this thread.. so here goes.
The pack was a total basket case, the factory will not honor a warantee, refund or replacement pack, even tho they promissed they would, but then changed their minds.., and FalconEV pretty much told me i'm SOL. So make the best of what you got. :?
The 48v pack had to be split into 2 .. so i have a 33v and a 12v pack.. minus 3v that canot be salvaged ( Big dent into the cell and the tab is ripped off at the edge of the cell..
The pack was a total basket case, the factory will not honor a warantee, refund or replacement pack, even tho they promissed they would, but then changed their minds.., and FalconEV pretty much told me i'm SOL. So make the best of what you got. :?
The 48v pack had to be split into 2 .. so i have a 33v and a 12v pack.. minus 3v that canot be salvaged ( Big dent into the cell and the tab is ripped off at the edge of the cell..
