| Battery Tips & Maintenance from SMC |
track testing has changed some of the methods below. We have
found that using a .07 peak detect for a 6 cell pack and a .05 for a 4 cell pack
gives good results. A 6 amp charge rate should be used and if you need more
power then you can go up to a higher charge rate. We have used as high as 10
amps with no negative effects. If extra capacity is needed then you might want
to go down to a lower charge rate.
Important:
To get
maximum performance out of your HV’s they must be warm/hot before you race
them. This is why we recommend the above peak detects. Start to charge your
pack and try to get it to finish it’s charge as close to your race as
possible. Repeak using the same setup as your charge.
Discharge & Storage:
After your
race or practice run bring down the pack to 5.40 volts for a 6 cell or 3.60
volts for a 4 cell pack at 30 amps. If you want to keep the maximum runtime in
your packs do not put them in a an equalizing tray. If your not concerned with
runtime then you can use an equalizing tray and you will pick up some extra
voltage but lose some runtime. If your pack has cooled for 2.5 hours it can be
reused without any drop in performance.
Good all
around method of maintaining HV’s is to discharge to 5.40 for a 6 cell or 3.60
for a 4 cell and leave them alone. Use them on the track 6 times or so. The
next time you plan on using them place them in a tray to equalize the cells
before you charge the pack. When the lights on the tray go out you should start
charging the pack. Use the pack for 6 or so times and repeat the process. This
method has proven to good on runtime and voltage.
Cycling:
We recommend that you don't cycle these packs to often they do tend to drop a bit if cycled to often. It's o.k. to cycle them once every 2 weeks. So far we have been using the following setup with good results. Set your T30/35 with a 1 peak charge at 6 amps with a .07 for peak detection for a 6 cell or .05 for a 4 cell. Set the discharge at 30 amps with 5.40 cutoff for a 6 cell and a 3.60 cutoff for a 4 cell. Due to the 1 peak charge the runtime will be 4-6 seconds lower than a 2 peak charge.
Charge:
We use a 6 amp linear charge with a .07 peak detect. If your charger doesn’t have adjustable peak detection then use the mode that the manufacturer recommends for nicads.
Repeak at 6 amps with .07 peak detect.
Discharge & Storage:
Discharge at 30 amps down to 5.40 volts (6 cell) or 3.60 (4 cell). Use the small voltage sensing leads to insure proper discharge.
You should then put your pack on an equalizing tray. Make sure that every cell is making a good contact and that there is no broken resistors or diodes in your tray. This is best accomplished by verifying each cell with a voltmeter.
Once every cell in the pack has been equalized you can remove it from the tray or you can solder a piece of wire from the negative to positive terminal while it’s still in the tray. This is referred to as dead-shorting and when it’s done correctly it’s beneficial to the pack but if it’s not done correctly you will hurt your pack. If you’re sure that every cell has been properly equalized then it can be successfully dead-shorted.
Cycling:
This is how you should setup your T-35 or T-30 for cycling. If you use another type of charger/discharger you can use this info and adapt it to your equipment.
Set charge screen for a 2 Peak charge. Use 6 amps for both charges with 120 second delay in between charges. Use .07 for the first peak detect and .05 for the second.
Use 30 amps for discharge with a 5.40 volt cutoff for 6 cells and 3.60 for 4 cells.
Make sure you use the small sensing leads or else your numbers will be inconsistent and wrong. Make sure there is no airflow around the pack and that the room temperature is consistent. This will give accurate results.
It must be noted that the T-35 is harsher on numbers then the T-30.
If these instructions aren’t clear enough or you have questions feel free to email me.
Charge: Use a 5 amp linear charge with the peak detection set at .07 volts. If your charger doesn’t have adjustable peak detection you must monitor the packs voltage and when it drops by .07 volts you must stop the charge. This will happen between 32-38 minutes when using a 5 amp charge.
You can re-peak your pack at 5amps before you go out and race. Set the peak detection at .05 volts or stop the charge once the voltage starts to drop back by .05 volts.
Discharge:
After a race or practice run you should discharge the pack down to 5.40 volts (6 cell) or 3.60 volts( 4 cell). Try not to dump the pack on the track under high loads this seems to hurt the cells. If you’re using a T-35/T-30 make sure to attach the small voltage sensing clips. This will insure a proper discharge.
Once the pack is discharged and it has rested for a couple of hours it can then be recharged and run again. Some racers have noted that the packs are slightly stronger on the second run of the day.
Storage:
If you plan on running your pack on a weekly basis you should store it once it has been discharged to 5.4 (6 cell) or 3.6 volts (4 cell). If you don’t plan on using for 3 weeks or more you should cycle it once every 2 weeks.
Cycling:
This is how you should setup your T-35 or T-30 for cycling. If you use another type of charger/discharger you can use this info and adapt it to your equipment.
Set charge screen for a 2 Peak charge. Use 5 amps for both charges with 120 second delay in between charges. Use .07 for the first peak detect and .05 for the second.
Use 30 amps for discharge with a 5.40 volt cutoff for 6 cells and 3.60 for 4 cells.
Make sure you use the small sensing leads or else your numbers will be inconsistent and wrong. Make sure there is no airflow around the pack and that the room temperature is consistent. This will give accurate results.
It must be noted that the T-35 is harsher on numbers then the T-30.
Want to understand what bigger batteries do for you? Go to Battery School 101