Joined: 25 Aug 2004
Posts: 21
Location: New York City, USA
quote:Originally posted by TEAM HELL BENT!:
Why i wanted to know is because my triton charger was charging a 4500mah pack and it was still charging when it had reached 5amps in the pack or so it sed thats how much it had put in.
The 4500mAH rating is nominal and can be higher or lower depending on how much the pack was previously discharged or had self-discharged during storage. There are also cell-to-cell variations that can affect how much of a charge they will accept before peaking. Our 3000mAH packs regularly take 3300mAH before peaking.
Also, charging isn't 100% efficient. You need to put more than the rated capacity of the cell into it to recharge it fully. Some of that charge is wasted as heat and some of it is used to overcharge the cell to detect when the charging has peaked.
Unless the pack is overcharged a bit, the discharger can't detect the drop in voltage when the charge is complete. This is why a peak-detecting charger is so important...otherwise the pack will overheat and be damaged. You want to just a bit past fully-charged, but not enough to damage the pack. _________________ John Muchow, CamLight Systems
http://www.camlight.com
Sat Aug 28, 2004 12:49 pm
timmeh Experienced Roboteer
Joined: 20 Jul 2004
Posts: 2523
Location: Victoria
Thanks i was getting worryed.
I just sent you an email as i noticed the the pdf docs from your site so i thought youd be the man and then after i sent the email to you i got one back from this forum and you had answered it lol _________________ Tim Team Reaper.
Sat Aug 28, 2004 12:56 pm
JohnMuchow
Joined: 25 Aug 2004
Posts: 21
Location: New York City, USA
quote:Originally posted by TEAM HELL BENT!:
I just sent you an email as i noticed the the pdf docs from your site so i thought youd be the man and then after i sent the email to you i got one back from this forum and you had answered it lol
Joined: 20 Jul 2004
Posts: 2523
Location: Victoria
Lol while i was typing the email to send to you you where allreday typing the answer _________________ Tim Team Reaper.
Sat Aug 28, 2004 1:54 pm
timmeh Experienced Roboteer
Joined: 20 Jul 2004
Posts: 2523
Location: Victoria
Dose anyone know where i can get some good battery bars from? _________________ Tim Team Reaper.
Mon Aug 30, 2004 7:27 pm
Philip Experienced Roboteer
Joined: 18 Jun 2004
Posts: 3842
Location: Queensland near Brisbane
I have bought from this company and found them good to deal with. Remember to look at the ex vat price. Multiply the UK pound by about 2.5 to get the AU price. http://www.technobots.co.uk/
Home > Battery Products > Ni-Cad > Ni-Cad Bot-Packs Build Your Own Bot-Packs
Tue Aug 31, 2004 3:45 am
timmeh Experienced Roboteer
Joined: 20 Jul 2004
Posts: 2523
Location: Victoria
How many amps can they take?
Dose anyone know a web site or the specs on POWERTECH 4500nimh c cells? from jaycar _________________ Tim Team Reaper.
Tue Aug 31, 2004 6:18 pm
timmeh Experienced Roboteer
Joined: 20 Jul 2004
Posts: 2523
Location: Victoria
Just a tip for soldering wire or tabs on to batterys use BAKERS SOLDER FLUID it makes it a whole lot easyer just dab a bit on where you want the solder to go and solder "It fizzez a bit then sticks real good it stops the solder going all over the place other then where you want it to go but dont dab too much on as it will rust the battery termanal a bit you can find it in plumbing stores if i remember correctly its about $8 for 250ml it lasts you a very long time. _________________ Tim Team Reaper.
Wed Sep 01, 2004 8:58 pm
kkeerroo Experienced Roboteer
Joined: 17 Jun 2004
Posts: 1459
Location: Brisbane
quote:Originally posted by Team Hell Bent!:
Just a tip for soldering wire or tabs on to batterys use BAKERS SOLDER FLUID it makes it a whole lot easyer just dab a bit on where you want the solder to go and solder "It fizzez a bit then sticks real good it stops the solder going all over the place other then where you want it to go but dont dab too much on as it will rust the battery termanal a bit you can find it in plumbing stores if i remember correctly its about $8 for 250ml it lasts you a very long time.
Bakers Solder Fuid is a type of flux. It is a corrosive that helps soldering by cleaning any oxidents off the metal to be soldered. I use it a lot for soldering larger jobs like heavy guage wire. Do not use it for smaller stuff as it is a corrosive and will damage sensitive componants. Also watch out for the "fizzing" as fluxes are poisions so don't breathe the fumes, get any in your eyes and always wash your hands after use. And as it is a corrosive always clean any excess off or around the solder joint when finnished to prevent "rusting".
Another tip to clean surfaces to be soldered is rub with a pencil eraser. This will remove any oils or dirt, and can be done to copper plated PCBs.
You can also try solder paste. It usually comes in a tub or syringe and looks like a cream. Just apply around the joint to be soldered and touch with a soldering iron. The paste contains both solder and flux and is easy to use but can be a little expensive. _________________ Get Some!!!
Secretary of the Queensland Robotics Sports Club inc.
Last edited by kkeerroo on Wed Sep 01, 2004 10:19 pm; edited 1 time in total
Wed Sep 01, 2004 10:16 pm
Spockie-Tech Site Admin
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
quote:Originally posted by Team Hell Bent!:
Dose anyone know a web site or the specs on POWERTECH 4500nimh c cells? from jaycar
I've asked Jaycar staff to see if they can get me specs for their batteries on several occasions without success..
I suspect they are probably unbranded chinese batteries, and most chinese equipment manufacturers dont like people to know who actually made them if the retailer is buying unbranded ones.
I did some current testing on the sub-C 2400 hi discharge niMH's they sell, and my feeling is that they are about 2/3 as good as the equivalent sanyo's in terms of peak and sustained currents, which isnt too bad given the price. I dont know what their long term life is like in comparison though.
If you are going to buy a heap of them (50+), then get in touch with Jaycars wholesale division "Electus" and sign up for a wholesale account and you can get them even cheaper..
If you dont need the ultimate in performance and want to save a few $, they dont seem like a bad option. _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Wed Sep 01, 2004 10:18 pm
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
we have a set of these (2.7AH high discharge NIMH) in plan-B
we get great runtime out of one string at 14.4 volts
(we have 2 strings just to be funky though lol)
on 2 strings of 1.2AH nicads we are getting droop at the end of a 3 minute round and the fact we were running the nicads is the only reason there is any doubt over the mele outcome ;-P
Thu Sep 02, 2004 12:03 am
timmeh Experienced Roboteer
Joined: 20 Jul 2004
Posts: 2523
Location: Victoria
The pre made battle pack pages are gone from the R.M.P
You now have to design your own
And has anyone seen those AA 2100mah nimh sony cyber shot cells you can get 2 for $5
I wonder how good theyd be in a bot? _________________ Tim Team Reaper.
Thu Sep 02, 2004 5:44 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
i have those cyber shot cells in my digital camera.
the fact that there are AA says enough, but from personal experience of having 10 x 3000mah NIMH AA's in the first version of aurora, they suck when it comes to giving out current, they barely even turned the 550 weapon motor with a 150g piece of ali stuck on it.
Joined: 22 Jun 2004
Posts: 595
Location: Kurrajong, NSW
Looks like the cells actually sourced the current, which was the problem, as the rest of the pack couldnt handle it. _________________ Jeff Ferrara
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