Why does't the dual cell mod ever work for me?
 

I must be an idiot or something. This is my 2nd attempt. Here's the setup.

1 ZipZap with Microsizer PBC

2 ZipZap batteries

Instruction from QuestForMadness.com for the dual cell turbo mod.

I put everything together according to the instruction, stick it on my MODIFIED ZipZap controller which is putting out 2.73 volts of power according to my multimeter. Anyway, while chargin the car, I press give it some gas and the wheels fly so I assume everything is kewl. I let it charge for a minute, maybe a little longer and try to run it and it doesnt go. Its like it wasnt charged at all. Anyone know what the problem could be?

By the way, I tested the reading coming off of the pcb with both batteries connected and it was in 2 volt range.

I want to express that I have the SAME problem. I haven't tried new batteries yet, but the two batteries I have both work fine by themselves.

SOMEBODY HELP US PLEASE!!!

It's possible that when you soldered the battery to the other one it got too hot and fried the cell... How many watts are the irons you guys are using??? I'm assuming that you guts performed the controller mods as well.. If you use a hotter iron you can solder to the other battery before the batt. gets too hot inside.
I think that the surface needs to be around 250 degrees to get the solder to stick well, and with low watt irons by the time the end heats up the whole batt is smokin hot...

silla

My connections are good. I tested connectivity with my meter and have the proper voltage going thru. My batteries are fine when tested by them selves.

andramalech,
IS it a 3v NiMH? Or any other rechargeable? I used a 3V lithium today, but it wasn't rechargeable and at $5 a pop, they'd get way too expensive to use all the time. Li-Ion batteries are rechargeable, but they have to have almost exactly 4.2V to chrage them and they are very fragile. This means that a charger mod is almost impossible.

BTW, my iron is 30 W.

Thanks for the info, but I dont think any of that helped me. I cant believe anyone cannot comment on this problem. Maybe there should be a poll. If you have successfully got the dual cell mod to work, please let me know. If not, I'd like to know too.

fried batteries
 

this has happened to me a bunch of times
its pretty easy to fry the batteries
by heating them up
you have to be very careful

does anyone know of a source
for 1/3 aaa with solder tabs on them
should solve the prob

oink

andramalech,
Thanks for the INFO!!! Some good stuff you got goin there. I tried the 9V mod the day after I got mine (3 days after they came out :-) But I got kinda nervous because it was so much more juice... (And I couldn't keep the thing upright with that 9V taped to the top... it kept flipping over).

So does the 1/2AA fit ok? I didn't think it would. Also, what format are these? They are NiMHs are they? I can't imagine a NiMh having that much juice. I expect its a Li+ which is sorta of hard to make a good charger for since it has to be charged at almost exactly 4.2V . Let me know what you've found on this stuff.

joeNuggetz:
Check your batts again. I did check mine again and it turned out that even though they were holding charges by themselves, the charge didn't last. It was like this: I could charge it, and it would read good (that's why I reported earlier that both my batts were fine), but after I tried to use it, it was useable for approximately 1 second before it lost its entire charge.... It turned out it actually was bad. haven't got new batteries yet. Running off expensive 3v Lithium nonrechargeables for the few races I have til I get my replacements.

Hmm, I will try that axle. So, is yer mod working now? By the way, how many volts should be coming out of the modded controller to charge the dual cell? What if its less than expected, will that not work? Im a battery idiot. I wish I knew more of the ins and outs of charging these batteries.

I don't have my new batteries yet, so I have been runing a 3v Lithium camera battery for my races. That thing rocks :-)

I'm not sure what the charger specs should be, but I heard somewhere (I think on this forum?) that at least 2.2V and not over 3.2V for the 2.4 mod.

hello peoplez. i dunno if u folks solved your problems wit the dual cell mod but i followed some persons advice and soldered my wires to copper tabs and connected i that way to my batt'z. and shaabam no fried batt'z no hot iorn on batteries just make sure the contacts are touchin...:D