SMC 3800/4200 Battery Management

[RC51]

Hey, folks.

A number of you have been asking about battery management with the IB batteries from SMC. They are treated differently than the others that we have seen and used in the past and there is some conflicting information out there. So, Korgae has offered the following details for our battery care. Here you go:

From Korgae: With the 3800 and 4200 cells,  we are finding that a small amount of charge be put into the packs, when you are storing them for a few weeks or more.

If you plan to use them week to week, they will be fine storing them @ 5.40V ( .90 per cell) for the week in between the races.

Do not dead short them at all, this will harm voltage. The bit of charge over a longer storage only helps the overall runtime of the cell, it does not effect voltage in any way.

It is very hard to either improve or harm the overall voltage of these cells while following our charge and care instructions.

So in a nut shell:

Charge @ 5-7 amps ( we like 6)
Discharge the pack to 5.40 at a high amperage ( 30 or 35 amps)

Little extras:

Before charging you can place the pack in a good tray until the lights just go out, this will help the pack charge a bit better as it will not be ice cold.

Do not use a fan to assist the pack while charging, and please use a peak detect of 0.02 or around 24MV (a pack) and go from there depending on the weather temp.

There you have it! Thanks, Korgae.
Phil

[haddow]

holy crap a delta peak of 24 Mega Volts (MV) !! I tried that just now and it was like the 4th of July in my garage, cells popping everywhere, damn!

24 mV = 0.024 V
24 MV = 24, 000, 000 V

Just being a picky prick LOL

[haddow]

PS Thanx Phil (Korgae)!

hmmmmmm,thats what i was using for a 4 cell 3300 well i guess we will see as i beleive every charger is a little different as the charger i had before that would false peak at anything less than 8 mv a cell for nimh

[gearhead]

I had mine set at 7mV/c for 3800's and it almost (or maybe did) fry my battery, made the negative side of the cells bulge

[gearhead]

When you say down to 5.4 V do you mean under load on discharger or off discharger?
What is the reason for discharging that much?