battery discharging "?"

[CandyRedTC4]

Ok, I bought the deans light bulb discharger and the integy discharger/equalizer tray. They said this will help my batteries to last longer. I have the 3800 IB pro-match batt. the manual says to discharge it to 5.4 volts so I tried to do that and it took me about 2 hours discharging it and I accidently forgot to check the voltage and now after 2 hrs I removed it from the tray and read the Voltmeter, it was at 4.80+ Volts and I checked each cell and one of them is 0.0 volts. Is this very bad for the cell? Did I just messed up one of the cell?

Do I really have to drain it down to 5.4 volt on each battery packs I have (I got 8 packs) Can I just drain it on the deans then I'll let the light run out on the discharging tray then pull it out?

i spent alot of money on my batts,charger and discharger. I was just wondering what is the best way of keeping the batteries in almost new condition.

Thank you.

[highroller]

Let the pack sit awhile then try charging it again - it may be fine.
Install a cutoff device (Racers Edge avail direct or on Stormer Hobbies) that cuts of when cells reaches a .90 volt level. Store the pack at that level, (5.40 volts for 6cell, 3.60 volts for 4 cell) before using the pack place it in equalizing tray then remove once the bulbs go out or within 10minutes. It won't hurt the cells if they are left in longer, residual voltage should build up once pack is removed.

Dead shorting, deep discharging does not seem to provide any benefit to the IB3800 like it does to GP3300/3700 cell. Some suggest putting a 10min charge in pack if it won't be used for two weeks, more charge for much longer periods but discharge/equalize the pack before using. I just leave packs discharged to a .90 volt level regardless, only noticeable difference is pack seems soft or flat (no punch) for about the first three cycles. Some have a concern regardling a lost in runtime, that is the reason for recharging pack for storage or length of inactivity. For stock racing I feel leaving pack discharged is fine, the runtime isn't that great or cause for concern plus as long as pack is used frequently it stays pretty consistant for me.

Normally you want to check voltage levels of cells while they are being charged or discharged. Using simple things (bulbs for discharging, stopwatch, paper) you can get a rough idea of the condition of the cells. Charge the pack average the voltage by number of cells with individual cell voltage, and do the same when discharging - taking voltage reading of pack every 30 seconds or 1 minute intervals until voltage is 5.40 volts for 6 cell or 3.60 volts for 4cell. Individual cell voltage may have to been taken roughly every two minutes. Good cells should not vary more than 5 points, 10 points and greater are usually signs of decline.

[rigrishracer22B]

are you suppost to discharge nimh batts?can you trickle chrge nimh? and what is the best way to discharge nicd? and at what rate can you charge them? thanks :D

[highroller]

The idea of deep cycling cells (equalizing) came about from racers, battery matchers experimenting with the early Panasonic NIMH. Contrary to information, cells responded better if they were first discharged at levels seen in use, then discharged with a lower load of 1-2amps until cell voltage was around .25 to .10.
Fast charge packs used to power vehicles, rates vary depending on max output of charger or what pack is being used for. Lower rates take longer for pack to reach a peak level but you gain some added runtime (3-4.5amp rate) but loose of a little of the punch - cells may last a little longer, rate of 5-6 amps increases the voltage (punch) output, but at a decrease in runtime. While some higher rates are used to increase punch or voltage it may cut the life span of cells. Nicad to should be discharged after use to a .90 volt per cell level, normally close to loads it subjected to while in use can be taken to a zero level (hi grade cells) without harm if done correctly using a discharge or equalizing tray. Only the GP NiMh can be taken to very low voltage levels without harm - oval racers in the stock and 19turn classes would dead short the pack (once voltage was at a safe low level) which normally increased voltage, kept internal resistance low but may affect runtime greater. The other types IB3800, IP3800, Sanyo 3700 (race situations) respond by leaving in discharge tray until lights go out or each cell is around .03 to .15 volts per cell.
Only cells I generally trickle charge are the AA cells used to power radio, or those receiver packs used to power the receiver and servo. Sometimes they have to be fast charged but at much lower amperage rates of .05 to .50 amps.
The reason for discharge is for several reasons, rechargeable batteries seem to respond better by removing the remaining charge left in them, time should be allowed to chemicals to cool first before recharging. By removing voltage cell is able to fill back to normal (cell may build a memory even NiMh, go very well at the top of charge then taper off - when cell reaches the point where it was partially used the time before). Also NiMH are a little more prone to causing false peaks as cells discharge to different levels over use - that is one reason for discharging then equalizing each cell.
How and what you do kinda depends on several things, whether you are just bashing, or getting into racing competitively. When racing you generally want consistancy and things are done to get consistant results - plus it changes a little with the type of racing you do.
Read some of the informations some of the battery matching companies have on their sites, while most is for racing use it can be adopted and used for bashing but without the high priced equipment.

[rigrishracer22B]

do you race If you do what is the best car youve raced

[highroller]

Yes I do race, but race packs are handled differently (based on type of racing) than the packs I just use for bashing. Offroad/TC packs are charged at 5-6amp discharged at 25amp, usually packs are discharged then stored, packs used in oval racing are handled differently stock/19turn charged at 6 or 7amp discharged at 35amp, modified packs charged at 5-6amp, then discharged at 35 amp. Packs used in bashing are charged at 5amps discharged around 20amp, use a single 1157 bulb or Cobra Battery Bug that were available years ago to equalize stick packs or bashing packs.

Equipment is a little more high tech for racing, CE GFX charger, Integy Zero30 used the Integy Octane2 or Trinity Real Time 2 & 2.5 equalizing trays.

As far as brands go, I owned and race several sometimes one was better suited for track layout but generally it was kept to one or two brands because of parts issues. Most vehicles perform well in the stock (team version) without the need for upgrades, but pan cars (12th and 10th scale) AE car are usually upgraded - sometimes never using a AE stock item.

[desfjr1300]

In your post above you mention using a single 1157 to equalize a stick pack-Can you explain that please? Is it just a matter of soldering a connector on then plugging it in for a certain amount of time? (based on MAH?) How does that equalize a pack?

[highroller]

The auto taillight bulbs are rated for 12volts with a approximate load of 2amps for each bulb. Some use a varing amount usually 10 for a 20amp load but when deep discharging a pack or cell you want to do it at a lower load, so 1 bulb works fine stick packs and it's the cheaper way of doing it without having to purchase expensive dischargers or equalizers - it's not a 100% method as it doesn't discharge each cell.
If your pack uses a standard tamiya plug you need the opposite end - some come prewired, just stripe away 1/8 to 1/4 inch of the coating tin the ends (heat and apply solder) then solder the positive to the top (usually there are two contacts on top, solder the negative to the side. Both elements (dual element) should be bright depending on voltage left in pack, but bulb will start to dim as pack voltage gets lower. If you have a DVM (digital voltage meter) touch the contact with prob, when voltage is around 1.50 volts (.25 volts per cell) the voltage is low enough. A 1ohm, 10watt discharge resistor will accomplish the same thing as well, since the resistor is non polarize it doesn't matter which end goes on pos or neg. The resistor will get warm to hot depending on amount of voltage left, once the resistor cools voltage it low enough - remove the plug with resistor from pack.

The amount of time it takes for bulb to dim or resistor to cool with vary depending on amount of voltage left in pack.

[desfjr1300]

Thanks Highroller! I normally use side by side packs that I can put in the equalizing tray, but since Radio Shack started selling cheap GP3300's I've managed to accumulate a few that could probably use some TLC. Off to the auto parts store I go!