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holy_inferno
06-23-2005, 11:02 PM
When I charge my URC 1100 gp8-cells using my MRC charger (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXEVC7&P=0), It always charges over 1100 mAh and it still doesn't detect the delta peak set low as 15mV... Is it over charging my batteries, or does the charger always charge more than the rated capacity of the battery pack... I still have great performance and run times from the packs, but I fear that I may be over charging and damaging them :(

Help please.. :)

.5x8
06-25-2005, 11:08 PM
well...chargers charge a little bit over sometimes...but what amp are u charging at? im charging at 1...nothing higher than 2 i read...i read on r/c tech that batteries overcharging a bit is kinda normaL? or did i read it wrong? iono...hmm....do u let the batteries cool down before u stick em back on the charger? try that...just lay it ontop of the fan..and it should be cooled in about 3-5 minutes..then charge it..if u already let it cool down..hmm IONO lol this is weird...maybe theres something wrong with the charger...maybe it cant sense the peak because something is wrong...hmm...email MRC about this..maybe they know.

holy_inferno
06-26-2005, 12:31 AM
...My charger does sense peak when I charge my NiCd pack...I let my batteries cool down for quite a while before I recharge them...and I charge at 1.5 Amps...

Wonder what is happening...does anyone here have my kind of charger?...Almost looks like halfEIGHT has one...http://halfeight.com/gallery/showphoto.php?photo=254&cat=525&page=1

Help would be appreciated :)

akura2
06-26-2005, 12:33 AM
Well my 8-cell pack always charges to almost 12v before the charger shuts down.... the batteries actually hold way more than their peak voltage right after the charge, then level off with use... that's why you should top off your batteries before a race because you'll get extra punch for the first few seconds... in other owrds...don't worry about it unless the batteries are getting abnormally warm

holy_inferno
06-26-2005, 01:43 AM
Ok, thanks...by "abnormally warm," how warm is it?

:)

mOOsE
06-26-2005, 05:54 AM
Nimh batteries should not exceed 135 after fully charged...any hotter will diminish cell life. batteries may get hotter when in use but should not reach this temperature when being charged. Voltage will get very high as acura said and can even be intentionally higher if you charge with higher amp rates. Millamps Mah will sometimes be higher but good stop point is at the rated capacity.

mOOsE
06-26-2005, 05:58 AM
I also didn't notice that you are using gp cells. GP cells are rated for higher amp discharge so you can charge them higher too. Part of the problem may be that you are ONLY charging at a measily 1.5 amps. I would try 2.5 and that should assist your charger in picking up the voltage dropoff.

JuJuB
07-01-2005, 03:23 PM
Is discharging REALLY nessisary

holy_inferno
07-01-2005, 03:44 PM
Is discharging REALLY nessisary

...Not really, with NiMh batteries... I think :)

Why you ask? :confused:

JuJuB
07-02-2005, 07:18 PM
I just read in other threads on other websites that discharging your batter pack will eliminate cell memory and that I should discharge my cells every now and then.

Hawk
07-03-2005, 01:39 AM
cell memory is a NiCAD problem that is mostly taken care of in NiMH batteries. :cool:
and LiPo batts forgot what happened 5 minutes ago. :D

BitHed
07-03-2005, 01:48 AM
...SideNote: Apparently chickens take 3 steps and forget what happens...MythBusters proved that goldfish have a memory...Pity I cant remember what I had for dinner last night :o

akura2
07-03-2005, 01:25 PM
seaweed nibbles?

Hawk
07-03-2005, 09:34 PM
:D
seaweed nibbles? :D
U talkin bout BitHed or the goldfish?
:cool:

BitHed
07-03-2005, 09:38 PM
...he that nibbles seaweed KNOWS he is going insane..lol...damn it took me ages to figure Akuras post out...I need a vacation in an English speaking country lol...

Hawk
07-03-2005, 09:43 PM
Just be thankful that people aren't asking you "Is that a battery in your pants or are you just glad to see me?" :cool:

plain_simple
07-04-2005, 12:31 PM
i agree with Moose and you should also discharge them at 0.10. That will help on the memory area and will give more runtime ;)

Inferno454
07-07-2005, 04:15 PM
Hey! I like seaweed nibbles with a side of cavier every now and then.

TNB
07-07-2005, 06:41 PM
When I charge my URC 1100 gp8-cells using my MRC charger (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXEVC7&P=0), It always charges over 1100 mAh and it still doesn't detect the delta peak set low as 15mV... Is it over charging my batteries, or does the charger always charge more than the rated capacity of the battery pack... I still have great performance and run times from the packs, but I fear that I may be over charging and damaging them :(

Help please.. :)
I would dump that MRC 969. I own one and it sits on a shelf collecting dust. First, the power supply went out at RCX 2004. Then the replacement power supply started acting up one month later though MRC replaced it at RCX 2004. Others I know have also had the same problem with it and have cooked NiMH. I also mentioned it to MRC at Hobby Visions 2004, but those reps just blew me off unlike at RCX 2004. However, it could have been since I was surrounded by other racers at RCX 2004 and was not at Hobby Visions 2004.

Currently, I use the Triton, the Novak Millinium Pro, a Thunder Power lipo charger, and a Radio Shack AAA charger for those slow nights when running Zs and not running lipo powered brushless motors. ;)

halfEIGHT
07-10-2005, 04:23 PM
I use a 969 and haven't experienced this issue. :)

holy_inferno
07-10-2005, 04:50 PM
halfEIGHT, what settings do you use when charging your battery pack for the Mini Inferno? What's the maH and Voltage rating on your battery pack when your charge is complete?

Thanks :)

halfEIGHT
07-10-2005, 05:18 PM
1.5A, 25mV; will check maH/V on my next charge! :)

holy_inferno
07-10-2005, 08:38 PM
Those were the settings I used to use...until I saw the charger charging over 1100maH, I got worried, so now it's 1.0A, 10mV, charges to 1068maH O_o
...Wonder if it's the connections to the battery are too long...banana plug/tamiya plug/deans/battery