rbecking

I've just got some SMC 4200 SHV cells.

So after a run should I discharge them at 20A to 1v each then use a Novak smart tray down to 0.9?

Joel Lagace

iTrader: (4)

treat them like the 3800s. drop by www.smc-racing.com and follow there guide

rbecking

Should I use a smart tray or not? I've read you shouldn't let them go below 0.9 and discharging whole pack at 20A to 0.9 risks going below?

Joel Lagace

iTrader: (4)

for my 3800s i 20amp and tray to .9 on smart tray before recharging

BSchorr

iTrader: (101)

Discharge at 20-30 amps. Tray to .7. .7 wont hurt them because they wont be sitting like that for very long.

If you get to the track early and have time to discharge the rest of the capacity out and tray to .7 and then let them totaly cool before you have to charge them for your first race.

But if you are hit up for time. discharge the packs to 5.4 volts that week. then let them sit for the week, when you come to the track, tray to .7, let kool(shouldnt be to warm). Then charge at 6 amps setting your delta peak to 10 or 15mV cuttoff (Much More Cell Master=5-6mV).

I was racing tonight outdoors offroad. It was cold out, like 65 or so. So i set my delta peak to 15mV. Pack was at 142 degrees. TO hot! Set it to 10mv 125 degrees! PERFECT

They say also not to put a fan on a battery when chargin or after your race(People who tell you do to this should be shot), Cooling ur packs during charge or after decreases your runtime and inscreases your internal resistance. Only kool ur motors after races with alittle DC fan if you got one.

Ben

L.P.I.

ive from running the packs.when your done with the pack for the day tray it .9 cutoff then after cool off put 1,000ma back in the battery for storage till next week.if u dont put a charge back in u take a chance on killing cells.and dont dis charge past 30amps.

porschejim911

iTrader: (6)

Can we get some more opinions on charging temp? I have always thought that 130 was about as hot as a cell should ever get. I've been having probs since I got my 4200 cells though in that it seems like 1 cell will go up to around 150 and then I stop the charge on the pack. Can these things really go up to 160 safely?

BSchorr

iTrader: (101)

[QUOTE=L.P.I.]ive from running the packs.when your done with the pack for the day tray it .9 cutoff then after cool off put 1,000ma back in the battery for storage till next week.QUOTE]
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Wrong.

You dont tray to .9 after a race, You can discharge it to .9 though... Traying would take forever and day. EAMotorsports want you to discharge it down to 5.4 volts and let it sit for the week, then when you come back the next week, tray to .7, THen coool, then charge!

For your Delta peak... IB's cutoff has changed dramatically from charging GP's. I charge 6amps with 10mV on my Pulsar Competition and it gets to about 125 degrees. I tried 15mV since it was cold out last night and the pack got HOT, 140 degrees. So I Put a fan on it for like 3-4 minutes before my race.

For 3800's and 4200, i would recoomend the Much More Cell Master charger. you can further clerify you cuttoff, if you want to read about hte charger, go on teh website

Skiddins

I use my Novak Millenium Pro to charge them and recently tried taking the pack off charge when it reach 9.1V (it usually completes a pack at about 9.25V).

By taking them off early the packs were only fairly warm, not hot.
This did seem to help keep the internal resistance down as my car had loads of punch.

I have also managed to let my batteries discharge too far using car bulbs etc then walking away on more than one occasion, yet they still seem fine (once, I checked the pack voltage with a DMM as soon as i'd ripped the bulbs off the pack, it read 3.4V for the pack and as this point the voltage was still 'recovering' rapidly).

Before use, usually the day before, I discharge whatever was left from the race day (racing Stock the packs still have half their charge left after a run) using a Spintec Battery Manager, I take the pack off when it's down to 6.7V then finish the pack off on the Novak Smart Tray.

I use the Smart Tray again just before I want to charge for the race.

Repeat....

Skiddins

vabroom

As always this probably has been ask, but who sells the SHV cells. I've been to a couple of sites including SMC and noone lists them.

BSchorr

iTrader: (101)

They arnt labled "SHV 4200's" The just got the pick name "SHV" They are the ones that are 1.230+'s

WorldCup2004

Team Orion is selling the SHV

Yeti35

iTrader: (5)

RaceDay RC is selling them and he has a whole batch of them in now cycling and ready to sell. The link for the site is in my sig. If you buy any from him tell him Yeti sent yah!! I got some the other week and they have some serious punch to them and I don't even have them broken in yet.

Yeti35

iTrader: (5)

My cells do have the SHV label on them and that is how they came in, not something my matcher did.

Fast Faisal

Where do you purchase your SMC's from?

Thanks
Fast Faisal