Got a 12.47V, 40Amp, power supply ... had to test it ... decided to push my repaired iMax B8, back up to 5Amps @ 29.4V.DrkAngel said:If you are getting the iMax B6 balance charger, be aware that various reports, find full 5amp charging to be "iffy". Recommend 2-3amp charging initially. Personally, my B8, blew a Mosfet at 5amps, 12v input - 29.4v output. Mosfet replaced, will test with higher input voltage, lower output voltage etc. Will post results. - May 2011
DrkAngel said:iMax B6 - $19.95 w/shipping
Requires 11-18V power supply.
Fortunately, I have a pile of Ibm 16V 4.5A notebook chargers.
Unfortunately, I'm never satisfied ... started playing with one of the Server PS I had laying around.
Now ... I have to find a use for 55A of nice, clean, reliable, 12V ... ?
iperov said:24v 5ah x 2
in QQ sports mini frame bags
I attribute the quality and survivability of this pack to the extra care I took in testing and matching cells!
All the "nickle strips" are spot welded oem.chilledoutuk said:I attribute the quality and survivability of this pack to the extra care I took in testing and matching cells!
That helps but honestly the quality of 18650 cells from the big manufacturers is what makes them so reliable.
out of interest what measures did you use to prevent the nickle strips cutting through the thin shrink on the pack you just showed and shorting cells?
DrkAngel: I'm confused. Sounds like your capacity is measured by the amount of energy going INTO the battery during charging. Is that correct? If so, why do it that way?DrkAngel said:The pack is a 7S12P, 3.7V 2160mah per cell.
With a 25.92Ah rating.
My iMax B8 balance re-charge, metered a 20.8Ah input.
Charging rate was 3A = .125-.15C, for maximum efficiency.
Giving a 80.2% , of rated, capacity!
Lithium Cobalt charging, at moderate rate, is 98-99% efficient, a good measure of capacity.SamTexas said:DrkAngel: I'm confused. Sounds like your capacity is measured by the amount of energy going INTO the battery during charging. Is that correct? If so, why do it that way?DrkAngel said:The pack is a 7S12P, 3.7V 2160mah per cell.
With a 25.92Ah rating.
My iMax B8 balance re-charge, metered a 20.8Ah input.
Charging rate was 3A = .125-.15C, for maximum efficiency.
Giving a 80.2% , of rated, capacity!
Those percentages sound impressive. But have you verified their accuracy?DrkAngel said:Lithium Cobalt charging, at moderate rate, is 98-99% efficient, a good measure of capacity.
...
, but lithiums, particularly Lithium Cobalt, at moderate charge rates, attain near 100% efficiency!
The Peukert effect is minimal on Lithium, especially at much lower discharge rate (less than 0.33C in your case I believe). But that's beside the point. Why not just use the Cycle Analyst for capacity measurement? After all, that's the only meaningful capacity as far as riding an ebike is concerned. No?DrkAngel said:A typical discharge, at varying discharge rates gives varied percentages of efficiency.
SamTexas said:Those percentages sound impressive. But have you verified their accuracy?DrkAngel said:Lithium Cobalt charging, at moderate rate, is 98-99% efficient, a good measure of capacity.
...
, but lithiums, particularly Lithium Cobalt, at moderate charge rates, attain near 100% efficiency!
Don't have one (Cycle Analyst).SamTexas said:The Peukert effect is minimal on Lithium, especially at much lower discharge rate (less than 0.33C in your case I believe). But that's beside the point. Why not just use the Cycle Analyst for capacity measurement? After all, that's the only meaningful capacity as far as riding an ebike is concerned. No?DrkAngel said:A typical discharge, at varying discharge rates gives varied percentages of efficiency.
CA is just an example. Any watt meter would do the job just as well.DrkAngel said:Don't have one (Cycle Analyst).
That's my whole point. I don't care about the OEM rated capacity (after all, these are recycled cells). I only care about the actual usable capacity of the pack when I assembled it, and its actual usable capacity now (after xyz cycles). But that's just me.DrkAngel said:Your ... typical usable capacity could be easily determined, but output, compared to oem rated, would have to be measured at a regulated, moderate drain.