Recent content by jeffkay

Greetings, I have an NG1 that has a label showing it is the 72v model however I purchased it from a guy who had it programmed (upgraded?) to do 96v. It says it has a 91v knee and was used for LFP lithium profile 24 cells of 40ah capacity. Now I have a 60ah capacity and 27 or 28 cells so I...

Hey Doc, You are assuming he has tabs. I don't think the China cells do...

See my posts on this link for how I did it: http://endless-sphere.com/forums/viewtopic.php?f=14&t=2764&p=59623&hilit=+a123+solder+pack+deep+cycle#p59623 Pack still works perfect! Jeff K.

Gary, Jack, Doc and all, I agree with the "fillup" principle after bottom-balancing. The problem I have with it is that the cell's health may not allow a good measurement taken "at rest--no load". A123's seem to wander around at rest more than TS or other chemistries I am using. Maybe in...

Can the backlight be forced to always be on? Seems a pain to light three of them, etc?

Hi, I am looking for CC/CV programmable (or at least settable) power supply that can do about 0-84vdc at 15 amps (again, current adjust would be nice). I would like some metering and a way to tell it at some voltage, change from Constant Current to Constant Voltage. Any links? If no, maybe...

Interesting use of peel-and-stick floor tiles! I made a Sony/Konion pack wrapped in vinyl "runner" material found at Home Depot. It is very cheap but has ribs and is very strong and non-conductive--and cuts easily. I have had it for over a year and no puncures. The outer skin is "Stucco...

Check out my son's bike--it is DC and not an RC motor but we ran into similar issues. By the way, the huge motor sticking out caused no issues with balance or obstacles. We could never figure out a usable kickstand for this bike though due to the weights... Jeff http://www.evalbum.com/1314

Yes, I meant in a different configuration. I will look upon the data sheet. Wonder what temp % tolerance that is. Might be in the data sheet as well. Thanks

Hi Gary and all, I am going to be using the opto side of my BMS for another project of sorts... I am wondering what is the range of measurable voltage from the output side of the opto chip and how linear is it? So would it be able to report 2 volts to 4.5 volts and what kind of curve is there...

Interesting project! I have two questions. Do you have a set of curves ffrom the motor manufacturer? Also, Is there any possibility to use this with side-loading? In other words, one arm and an axle through? Oh, and what is the diameter of your proto wheel axle-center to trread/pavement...

I am referring to the circuit board design shown in this thread... I note that the power resistors will have the potential to have their leads broken over time. This would be due to metal fatigue from vibration as the body mass of the resistor moves. Just a thought. Jeff K.

PJD, Yes, I agree a bms is good to have. I use Richard/Gary model as well. I forgot to mention that under heavy loads (car 300A plus) they will get out of whack I suppose... Jeff K.

Guys, I have a TS charger from Elite. I use it on A123, TS and LiMn cells with no problems. Yes, you don't get the full energy density of as if you charged higher. This is good and gentle to the cells! And the charger is rock solid in operation. By limiting the charge voltage the cells...

If you go to: http://docs.google.com/# and upload the saved file from Gary's zip, you can use the online spreadsheet if you don't have Excel... Thanks for this resource Gary! Jeff K.