The AAA Lithium Ion Batteries open up some real possibilities, and the Mini-Z AWD was the first on my list of cars to upgrade to Lithium power. This modification isn't technically difficult, but requires some skill with a Dremel tool.

Your NiMH cells are 1.2V each and in the 4S configuration they provide a nominal voltage of 4.8 Volts (1.2 x 4 = 4.8V). This is fine for NiMH, but if we put the Lithium cells into the holders in the 4S configuration, we would end up a nominal voltage of 14.8 Volts (3.7 x 4 = 14.8V) which would toast your mainboard in a hurry. So we need to change the battery holder to a 2S2P configuration. The 2S (2 cells in series) part of the equation will provide a Nominal voltage of 7.4 Volts (3.7 x 2 = 7.4). The second set of cells are the 2P (2 cells in parallel) part of the equation and run in parallel which does not increase the voltage, but instead doubles our available current and run time. If our cells are 320 mAh than putting them in parallel will give us 640 mAh pack. It sounds complicated, but don't worry, the wiring is the easy part.

Take your time and follow the procedures outlined here and you will be rewarded with a much more powerful Mini-Z AWD that appears to be stock, until you blow past your buddies like the Road Runner on crack - Beep Beep!

1. Solder
2. Soldering Iron
3. Flat Nose Pliers
4. Wire Strippers
5. Side Cut Nippers
6. Hobby Knife
7. Phillips Screwdriver
8. Flathead Screwdriver
9. Mini Meter Pro
10. Helping Hands
11. Safety Glasses
12. 22 Gauge Wire
13. Dremel Tool
14. 1/8" Cutter Bit
15. AAA Lithium Cells

Unless you are fond of fireworks, now would be a good time to make sure the power switch is off.

Since Lithium cells are "Flat Tops" without the usual button found on NiMH cells, they don't make contact when we put them in the holders.

Here we can clearly see the 1/16" gap between the contact and the battery top.

We must modify the holders to accommodate the Lithium cells by trimming away the plastic surrounding the positive battery contacts.

You will need a Dremel #191 1/8" Point High Speed Cutter bit or equivalent. I tried a few and this one is as close to perfect as it gets. Extend the bit about as far as you can and have it safely seated.

We are going to trim away the plastic as indicated above in step 4. Use the Dremel's mid to high speed setting depending on your preference.

You simply let the bit ride on the metal battery contact lightly to keep it steady and work your way around.

Clean it up with a hobby knife and this is what it should look like now.

Now we have good contact.

We just keep repeating this process on all the positive contacts.

Again ride the cutting tip on the metal to steady it and follow the pocket around.

Clean it up with your hobby knife.

This is what it should look like after clean up.

Again we have good contact after trimming the battery holder.

Repeat the process again.

Same trick, follow the plate around.

This is getting too easy.

Clean again wit your hobby knife.

This would have been a good picture if the AtomicMods logo wasn't in the way. If it weren't for the losers that leach our pictures, we wouldn't have to do that.

The rear inside battery contact is awkward to get to, but we aren't going to let that keep us from our Lithium powered wet dreams now are we?

We need to drill an access hole in the top of the car as shown.

Here is a shot of the hole, which is about as wide as the case ridges there.

Now we are going to press the rear inside battery contact out of the car. Be careful to press on the solid part of the rear end and not the center of the battery tray which is very thin.

Using our new hole and a flat screwdriver, push the battery contact out the bottom as shown.

Remove it completely.

Now we simply repeat the process, but we cannot use the metal as a guide so be careful to control your tip and don't cut too deep.

Take small cuts and check your work. You can work from the factory hole in the bottom and our new access hole in the top to get everything.

When you are done the battery should slide all the way to the plastic wall as shown.

Remove the battery and put the contact back in place with your flat nose pliers.

The battery holder is still wired for a 4S configuration so we need to make it a 2S2P now.

Use your Flat Screwdriver to remove the front lower contact as shown.

We need to separate this into two contacts.

Take the contact and give it a good strong pull with your Side Cut Nippers.

Now take the contact and bend it back and forth a few times to complete the process.

We now have two separate contacts as shown.

Now take your wire strippers and make a cut as shown.

You bought all these tools from us right? :)

You simply need to trim off about 1/8" or so as shown.

Now using your wire strippers, trim a small piece off the corner at 45° as shown.

Look ahead at steps 36 and 38 for clarification.

This is what it should look like when complete.

Now put it back in with your flat nose pliers.

Observe how the section we removed is oriented.

We are about to put a hole there.

We need a hole for our new wiring to exit.

Cut through the area of exposed plastic.

Clean up the hole with your hobby knife.

You missed a spot.

Here is our brand new wiring hole.

Put the tab back in to check clearance.

Our SuperFlex 18 is too big for this so use some 22 Gauge wire.

Its time to break out your Helping Hands to tin the lower tab.

Solder the red wire onto it.

Tin the upper tab, which is the one with the 45° cutout.

A close-up of the tinning job.

Bend the black wire at a 90° angle as shown with your flat nose pliers.

This is what the wire should look like.

Solder it onto the upper tab as shown.

Here is the upper contact after the wire has been soldered on.

And the lower tab looks like this.

Now we re-install the lower tab as shown pushing the wire through our new hole.

This is how it should look now.

Now do the same with the upper tab.

It will be a bit more stubborn, so break out your flat nose pliers.

Pull the red wire around to make contact with the inside battery wire connection point and cut it to length with your Side Cut Nippers.

See step 63 for clarification.

Cut the negative wire as well.

See step 63 for clarification.

Strip and tin the wires.

Hold the wires steady with your flat nose pliers and solder them in place as shown.

Here is the completed wiring, and with that we are now in a 2S2P configuration. Don't you feel good about yourself?

Now we are going to make sure we are getting good contact on each pair of cells. Make sure the power switch on the bottom of the car is off and insert the inside pair into the holder as shown.

And now using my favorite tool, the Mini Meter Pro, we will check the voltage. It should read approximately 7.6v and it should be positive voltage as shown.

If you don't get a good voltage reading chances are a cell is not making contact and you may need more trimming.

Now insert the outside pair into the holder as shown.

And again using the Mini Meter Pro, we will check the voltage. This also looks good.

If you don't get a good voltage reading chances are a cell is not making contact and you may need more trimming.

Now that we know the wiring is correct go ahead and install all 4 cells as well as your antenna. Be sure not to use a long screw which could reach down into the battery compartment and short the antenna wire out on a battery.

Now you are ready to test it with your radio.

Grab your radio, switch the car on, and test it.

Congratulations you lean mean Lithium installing machine.

Look at that sleeper!

Now go and spank your unsuspecting buddies at the track. They will never know what hit them, trust me I know - Rob

The plastic tabs we removed prevented the Ni-MH cells from making contact if they were in the wrong orientation giving you a failsafe. Without these it is very important to observe the proper battery orientation as you can toast your board if you get it backwards. The factory battery markings are intact and the cells go in exactly like the original ones did, so check it twice before you turn the car on.

To charge these cells with our Lithium 7.4V, 500 mAh Charger you will need to put them into a 2S2P configuration. Our FlatRack AAA Battery Charging Tray is a good solution for this.