theisgroup

iTrader: (10)

big thing is to check the temp. you may not have put a full charge into the pack. I have 3 month old ib3800 and they still take in 4300-4400mah. and I take my cell off at 120 once then hit for a little after peak, they get to a high of about 125. I know most are looking for 130-135.

daniz24

Muchmore IB3800 are matched or only zapped?

Still Bill

iTrader: (16)

Nick,

You likely will not get the performance you are seeking until you have run the packs a few times (4-5).

Follow the instructions for charging your 3800s. They are not the same as 3700s.

BATT_MAN

Nick,

I am sorry that I did not get back to you sooner.
You will receive all the info you requested this week.
I will explain why when we talk later.

Now, regarding your batteries...
Depending on how IB's are enhanced and or cycled, the performance will change during the first 5 to 7 runs. However, in my experience running time is not a factor.



Here are some questions that if you answer might help me guide you.

What is the running time on the batteries and at what rate?
What charger are you using and at what settings.
Did you cycle your batteries before you raced for the first time?
Have you discharged your batteries, and if so what did you do (how long,to what cut off, which discharger) ?
How long did it take you to solder the battery tabs and did the batteries get extremely hot during this process?
Are there any white deposits on any cells (on the + tab)?
Do you see any discoloration on the positive side seal. It might look like its wet in some areas and/or deformed.
What motor are you using (winding, timing, brand, etc)?
How many amps is it pulling under no load.
Are the batteries hotter than the GP3700s right after you finish the race?
Do you know what the peak charging temperature is?
Have you noticed the millivolt differential from PEAK CHARGING voltage to the voltage when the charger stops (the pack will reach a high voltage and then it will star coming down untill the charger shuts off)?

There is a known problem with motor magnetic oversaturation but this does not cause a pack to dump or loose as much energy as you are, you just loose power and punch. The pack seems flat, but the majority of the times it is not the IB cells but the motor that gets too hot, oversaturates, IR increases, and performance drops exponentialy with the increase in temperature.

Assumimg that a motor pulls on average 30 amps, for an IB3800 to be dumping at 4.20sec the pack only has a capacity of only 2160mahr +/-. Most IB's are above 4000mahr. You are at 54% capacity.

Either you are not charging your batteries to their full potential or there could be damaged cells. These numbers are WAY too low. Even if your motor pulled 40 amps average, the cell capacity would be at 2890 mahr +/-... Still too low. 1000 mahr lower than average...

On average, IB3800s have HIGHER capacities than GP3700s and thus longer running times and overall output power.

One note, many people damage IB cells when soldering them. Many times when users accuse the matcher the problem is either caused by over heating the cells by soldering, charging, or discharging.

Hopefully with this info I might be able to figure out what is happening.

We are getting IB3800s in the 4100+ mahr range and have not had any dumping problems at all. Even in high traction, 8 minute, modified 1:12 scale.

Our AX3 cells start at 4125 mahr and running time has not been an issue. As a fact, the last laps are just as fast as the start.

Please keep me posted as I will do my best to help you.

Again, sorry for my delay on gettin gback to you.

Isaac

sitting duck

Hi,

You can read a lot of things here on RC-TECH and its start too confusing me because everybody says differente things.Some say that IB 3800 may come under 0.9V som say 0.5V some say that it doesnt hurt to go below it if its not to long etc...
I have a robitronic disharging tray which discharges at 1 amp and it cuts of at 0.8 volts. I always disharge my packs the day before the race to 5.4 volts and then i tray them. It takes several hours for the lights to go completely of so the voltage will be a long time under 0.9 volt.One time left the packs in the tray for a whole night and the where 0.75 volt.
Will it damage the cells to keep them a whole night at 0.75 volts?

fjm9898

iTrader: (11)

batt man when will you be putting out the cut off protection for integy 030?

nnick

iTrader: (1)

-- josh69162: I get the same advice from other people I'll try it next time


-- theisgroup: next time I'll check the temperature too. stop charging when reaching 120F right?. Ambient temperature was VERY low 5-6C I don't think I can reach the 120F

--daniz24 : they are zapped and matched. the packs are their best

--BATT_MAN: ouaou many questions

What is the running time on the batteries and at what rate? I don't have them with me. I gave them to a friend with CFX to cycle and see what numbers they return
What charger are you using and at what settings. Much More CTX: 6Amp 0.05delta peak 45C
Did you cycle your batteries before you raced for the first time? NO
Have you discharged your batteries, and if so what did you do (how long,to what cut off, which discharger) ? I haven't cycled before run them. After run I put them on my Spintec
How long did it take you to solder the battery tabs and did the batteries get extremely hot during this process? I don't think the problem was soldering. time was very short and batteries didn't get extremely hot (I have very good solder iron - finally)
Are there any white deposits on any cells (on the + tab)? haven't noticed. will it be still there?
Do you see any discoloration on the positive side seal. It might look like its wet in some areas and/or deformed. not realy
What motor are you using (winding, timing, brand, etc)? 8x2 lrp (ti based), trinity long life brushes, hard sprind +/-
How many amps is it pulling under no load. haven't checked!!
Are the batteries hotter than the GP3700s right after you finish the race? can't really tell!! ambient temperature was very hot and could understand which was hotter or not. I think GP were! my laser gun is broken
Do you know what the peak charging temperature is? no. I had the temperature probe on my much more battery warming tray
Have you noticed the millivolt differential from PEAK CHARGING voltage to the voltage when the charger stops (the pack will reach a high voltage and then it will star coming down untill the charger shuts off)? as fas I remember it was normal

Isaak, I hope my answers will help you understand what I did and if there is any problem.

Thank you all

Nick

Danny/SMC

iTrader: (2)

Everybody seems like they have an opinion on this matter. Here is what I reccomend and know that is works well.

Discharge the pack down to .90 per cell at 30/35 amps after a run. Leave the pack alone until the next time you use it. Prior to charging it place it on a tray. I personally use the Integy 0-30 and place my packs on it for 1 minute prior to charging the pack. Some racers will use a tray like the Novak Smart Tray that has a built in cutoff. These style trays take a longer period of time to reach the desired cutoff so you will need to figure out how long it takes to make sure you still can get the pack charged in time for your run. Your 1 amp tray will take even longer.

Today I took out my IB3800s that I use in offroad and decided to cycle them to see how they held up using my above method.

The packs labels should add up to: 414-7.174-11.8

It cycled out to : 410-7.16-12.4

It must be noted that the room and pack temp was a bit under 70 degrees which will normally make the voltage look a little lower and the IR a bit higher.

This pack has been used 2-3 times per raceday which means I have had 6-9 track cycles on it and prior to racing them on the track I cycled the pack 5 times when I first built it. So after 11-14 cycles the pack has held up real well.

Danny/SMC

iTrader: (2)

After the pack has been discharged you should let it rest for a day or two and look at each cell with a voltmeter. If one cell has a lower resting voltage than they others it means that this cell has an internal short and your pack will dropoff 30-50 seconds early.

Still Bill

iTrader: (16)

Danny,

Looks like I missed your birthday on January 8.

Happy Birthday, kiddo.

JRX-S Bill

mojoman

iTrader: (11)

If I'm using a smart tray (which I do) what is the safe cutoff. I've been taking them down to 0.9 p/cell with the same effect as if I were just discharging and not equalizing. Will I damage the cells if I take them further regardless of time restrictions.

beerbarron

If anyone has some of the original IB's in the 1.18 range, and some IB's in the 1.20+ range then you know how much quicker the extra .02 volts can be. To try and get some more performance from my 1.18 pack I changed my normal routine. I would'nt do this all the time but it really seemed to kick up the performance.

1. I charged at 7.0 amps on my Pitbull. (Normal 6.0 amps)

2. I raised the voltage cutoff.

3. I covered the pack with a towel to retain the heat generated during charging.

I raised the cutoff to get a higher peak temp in the pack. Normally I set the voltage cutoff to yield a 130 degree pack. This time the pack peaked at 140-145 degrees. The performance was equal to my 1.205 packs. My lap times are normally .2 sec slower with the 1.18's but they were equal to the 1.205's this time. It could have been my exceptional driving, LOL, nope just the batteries.

Now, all that being said, I know Danny would'nt advise the above technique. For me the 1.18's are just practice packs now so what the heck, right?

rayhuang

iTrader: (5)

Danny,

Did IB make another small running improvement? I didnt want to buy new cells for the summer, but i am glad I did. More runtime than my "mod" packs and more voltage than my "stock" packs. Its crazy.


I guess its times like this I am glad I am not a GP distributer anymore cause I'd hate to be staring at 10,000 cells with 50,000 more coming no matter what!! You know what I mean. I for one am truly astonished at GP's slow reaction. I know we discussed it before how quickly GP would react if someone started to take a slice of their pie. Whats going on in China??

Ray

danjoy25

iTrader: (38)

Would charging IB3800 higher than 6 amps really give more power. Got 3 x 1.2+ packs arriving and need all the voltage I can get, as long as it last me 9 rounds in total for a 2 day event. 4 qualifiers in the 1st day and another 2 + triple mains on the 2nd day. (if I get in the A's )

Still Bill

iTrader: (16)

Apparently some of the pro drivers at the Carpet Nats thought so. I worked in tech and had to handle certain driver's cars VERY CAREFULLY to avoid being burned by their battery packs.

I don't go above 6 amps on my IB3800s.