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Deca
2011.01.17, 03:20 PM
Which probably isn't good since I've been flying electric RC for several years. I still have no idea if lipos are supposed to be stored charged or empty.

Anyway, I just got my Powerex C9000 Wizard One at our last race. I haven't actually purchased any batteries yet, but figured I'd ask here regarding how to care for them straight away.

What is the best way to utilize the various features of this charger? How should I handle/care for my batteries? Should I pay extra for matched sets or not worry about it? Is the break in function an absolute must before running new batteries? Basically anything that is helpful to know, will make my batteries perform better, and will keep me from prematurely destroying them, I would appreciate knowing :)

herman
2011.01.18, 02:30 AM
this might help...

Just How Important Batteries Really Are - by magicman (http://mini-zracer.com/forums/showthread.php?t=21099)

Maha MH-C9000 WizardOne Charger-Analyzer for 4 AA / AAA (http://mini-zracer.com/forums/showthread.php?t=24299&highlight=maha+review)

Deca
2011.01.19, 11:56 AM
This helps a bit, but I still have some unanswered questions.. How hard is it to match batteries? Is it worth buying matched sets because you'd need to go through so many normal sets finding batteries that match up, or will you generally be able to match a set between 2 packs of 4 batteries?

Why is it that lower capacity batteries offer more power, and is there any rule of thumb for selecting charge rates based on battery capacity? Should I discharge all my batteries after a session?

JuniorWKR
2011.01.19, 01:05 PM
i run team scream matched cells. here is my process to preparing my batteries for race night. Keep in mind everything i do i do using equipment that charges and discharges the batteries as a single cell. I never do any charging or discharging as a pack...

New batteries:
take outta package and charge on the powerx 8 cell charger. This charger charges each cell individually at a 1.2 amp pulse charge
let sit
discharge on the muchmore discharger to 0.7v. this discharger discharges single cells at 5 amps
let sit

repeat this process 3 times. this is the "break in process"

now for racing. i only use my race packs for racing. i never practice with them.

the night before racing i discharge all my bateries. for stock i discharge at 5 amps down to 0.5v, for mod i discharge at 3 amps to 0.7. the difference i feel is for stock the method gives more punch as it lowers internal resistance more and keeps the volts higher (this process will make the batteries as fast as possible but does kill the life of the battery, this doesnt matter to me, i just need to be fast), for mod im looking for a equalized pack for good runtime so i go a little easier on them...

the day of racing i charge all batteries on the powerx 8 cell charger while im at work...

then during the race night 5 mins before my race i use the imax b4quattro charger. i use this charger because it comes as four charger in one. so i made a tray that allows me to peak each cell individually... i peak at 3 amps with cut off at .5... this get the volts up good and high with a decent amount of mah going in to... after the race is over the battteries go back in the box and dont get touched again till the night before the next race where i will discharge them again... i hope this helps...

so to summarize it for you for race night prep
night before discharge
day of race charge
5 mins before race peak

i know this sounds like alot but trust me when i tell you i have tried everything... this process works with any race worthy aaa out on the market today... i even cycled through other racers battteries and there was no denying that my process makes even there used batteries faster... my method will get the most outta each individual cell which willmake the pack as fast as it can possibly be... when charging as a pack you will always over charge and under charge cells in the pack... this will never happen with the way i do it...

chad508
2011.01.19, 03:16 PM
JR 2 questions:
how long do you let batteries sit between charge and discharge?

also at what point are you grouping your batteries in a set? im assuming after the peak charge.

JuniorWKR
2011.01.19, 03:17 PM
during the break in i let them sit for about an hour inbetween...

the only time my batteries get grouped together is when they are in the chassis... others wise everything gets done as a single cell...

chad508
2011.01.19, 03:19 PM
what i meant about grouping was more about them into matched packs. our do you only use prematched cells. if so do you ever rematch

JuniorWKR
2011.01.19, 03:21 PM
sorry thought you meant something else...

when i match my own cells i do it using the discharger... after i run my break in i will discharge them, charge them, peak em and as soon as they are done peaking i throw them on the discharger... i group them by average volt and discharge time...

JuniorWKR
2011.01.19, 03:25 PM
the other thing i try to pay attention too is the volt drop when the discharger starts... this is why i like the team screams...

team screams have some of the lower volt reading from other batteries out there but what i like is unlike the trps and peaks which sit at a higher voltage when charged is when the discharger starts the trps and peaks drop lower then the team screams... so what this tells me is that the team screams can handle the burst better then the other batteries...

JuniorWKR
2011.01.19, 03:30 PM
lets just say that on a charge the trp's, peaks and teams screams all sit at about 1.4volts...

when the discharger hits the peaks and trps instantly drop to about 1.15 to 1.17...

the team screams drop to about 1.19 to 1.23 volts...

no i know this may not sound like alot on a single cell but put em all together and consider its a 5 amp draw on a single cell and not a pack and in my opnion its a huge difference.. and it shows on the track... i believe this is what gives the team screams such a linear feel to them..

EMU
2011.01.19, 04:12 PM
the other thing i try to pay attention too is the volt drop when the discharger starts... this is why i like the team screams...

team screams have some of the lower volt reading from other batteries out there but what i like is unlike the trps and peaks which sit at a higher voltage when charged is when the discharger starts the trps and peaks drop lower then the team screams... so what this tells me is that the team screams can handle the burst better then the other batteries...
I completely agree with this statement. The burst of power that the TSR cells have is some of the highest, especially in mod/super-stock classes. They are good in 70t classes as well, you just have to gear them differently than you would TRP/ATM cells.

chad508
2011.01.19, 09:23 PM
thanks for the good info. i have all the above mentioned equipment, i just have not been using it to its potential. i'll give the above a shot. thanks

JuniorWKR
2011.01.19, 09:28 PM
no problem.. if you need any more help getting setup there is a email link at the bottom of my signature... it goes straight to my blackberry so email anytime...

Mike Keely
2011.01.19, 10:37 PM
I also look for a low internal resistance while grouping the higher average voltage as the cell discharges. I do not worry about run time for stock racing. Stock is all about low IR and higher average voltage cells.

For mod I try to match for run time because the mod motors already have power so I just want the pack to have high capacity without one cell dropping way before the other cells in the pack.

JuniorWKR
2011.01.20, 11:36 AM
this is also true... sadly my equipment doesnt give a IR reading... But i do believe the IR will determine the discharge rate so if i group by discharge time i should be close on the IR

JuniorWKR
2011.01.20, 02:14 PM
hope we didnt scare deca away with our crazyness... hahaa... hope we answered your questions...

hpgod
2011.01.29, 08:52 AM
junior
Have you tried the new atomic cells Reflex has? Pure Power where do they stack up against the orions/team scream r1works.

I have not tried the new screams yet.

To date my fastest cells are 1 year old R1works 750s , They vented early on still kept on ticking.
I tried the TRP900 and they are my 2nd best
other that are ok Orion 1000 mod
stock orion 750s SHV

I charge all my cell at 2A. We race 70t locally but I do run mod when I travel to Myrtle beach.

JuniorWKR
2011.01.29, 01:06 PM
junior
Have you tried the new atomic cells Reflex has? Pure Power where do they stack up against the orions/team scream r1works.

I have not tried the new screams yet.

To date my fastest cells are 1 year old R1works 750s , They vented early on still kept on ticking.
I tried the TRP900 and they are my 2nd best
other that are ok Orion 1000 mod
stock orion 750s SHV

I charge all my cell at 2A. We race 70t locally but I do run mod when I travel to Myrtle beach.

i have not tried the atomic batteries myself... i have heard that they are very good for stock though...

if i could make a suggestion IMO i think a 2 amp charge is way to high... i would rather see you charge at one amp then peak at a higher amp before the race to get them nice and warm... when you get a full charge at one amp... you wont run the risk of damaging the battery at a 3 amp peak... it just gets em nice and warm and get the volts up... set the volt drop off to .5 on the peak...

i ran my team screams last night at club race and won 70t stock and 50t stock spec... i set the fastest lap of the layout sofar with a 8.7... fastest lap in mod right now is a 8.5... the team screams are really working nicely for me.. very linear feel to them... the are the best for mod... really makes it easy to get the power to the ground..