swtich

[megamighty]

Is there a switch I could use that will change quad pack in series to two dual packs in parallel? Radioshack? That way I could use the ZZMT controller charger because it's charging two dual packs at the same time. I wouldn't need to add cells to my remote, I wouldn't think.

Also, would I be able to charge dual packs in series with only four batteries in the ZZ remote? I mean four 1.5 volt batteries can charge four 1.2 volt batteries without a problem, right? Also, isn't it dangerous for the batteries to be recharged using direct current? Isn't direct current the setup that comes with the ZZMTs?

Thanks in advance

I built one of the ZZMT's that you're talking about. There are actually videos of it in the video section here.

There is a switch that can wire the batteries between series and parallel. You will need a DPDT (double pole double throw) switch to accomplish it.

The switches at RS are physically bigger than I like, but they do have them available. I cut out a section of the box of the truck to mount the switch. I charge it 3 times with the batteries in parallel.

The problem with the 4 1.5 V batteries charging 4 1.2V batteries is that alkaline do not always run at a full 1.5V. Likewise, fully charged nimh cells charge to about 1.3-1.4V. That charging process would be really slow and wouldn't guarrantee a full charge.

[megamighty]

So, I should use five 1.5 volt AAAs to charge four 1/3 AAAs. It's safe to directly connect the two batteries together without a resistor? Why wouldn't it cook the four 1/3 AAAs?

[megamighty]

Hi, I just added a fifth battery to my controller and connected the batteries directly to the charger base (did I need to do that?). I let it charge for about 40 secs and run it, but the discharge life only lasts for 30 secs before the truck gets slow. Do I need to charge it longer? If so, how long? Thanks.

The batteries in the ZZMT are meant to be directly charged. The resistance in the batteries is what causes the current to flow and charge them.

Originally, remember that 4 cells were being used to charge 2. Charging 4 cells with 5 is going to significantly reduce the time it takes to charge the batteries.

To have equal time, you would need to use 8 cells to charge 4, though I wouldn't recomend it. Personally, I would use the switch idea and triple charge the 4 cells when they are in 2S2P configuration or charge with atleast 6 cells for probably around 75+ seconds.

[megamighty]

Thanks, I attached four more cells to my controller and manually timed the charge. It took about 20 secs to charge the truck. I think I could have left it on there a bit longe, but I was afraid too much current was going in. I ended up dropped the number of cells in the charger to six like you said and that seems to work well. I think I'm going to stick with the six cell setup and not go witht the DPDT switch. It charges pretty fast, and I don't have to multi-charge it.

Also, I think I fried my reverse component of the truck. It just creeps backwards now when its fully charged. Is there a way to fix this? Do you think I could just replace a resistor or something.

Thanks