I have remade this to be smaller. please consider building this puck instead, as its smaller and much lighter, with still a notable increase in runtime

i needed an excuse for a new soldering iron to feed my keyboard addiction.

This is a battery puck made specifically for HTC Vive trackers, though Tundras and Etee support is planned eventually.

It supports Haptic Pancake, and is the lid is a remix of the plate provided. Dual motor for if haptics feels weak despite being full power.

The battery life improvements are:

• 2.0s to 12-14 hours from 3.5-4 hours
• 3.0s to 20-24 hours from 6.5-8 hours
• Tundras to 32-35 hours from 10-11 hours
• Etees to 16-18 hours from 5-6 hours

The components you will need are:

• (x1) EEMB 3.7v 2000mah LP103454
• (x3) m3 20mm screws
• (x6) m3 nuts
• (x1) 1/4" screw
• (x1) 1/4" bolt
• (x1) This step up, protection, and charging board
• (x1) 10mm haptic motor

There are only 2 solder points on this due to the stepup board used, however you could probably make them solderless.

The total cost is 🇬🇧 £12 - 🇺🇸 $15 - 🇪🇺 €14 - 🇯🇵 ¥2300 for all parts.

Any improvements would be great, especially those reducing thickness or size of the puck!

I haven't tested if using the Vives pogo pins (pins 3 (5v in) and pins 2 (gnd)) will work, as i was having my trackers turn themselves off when charged via the pins. If it does work, let me know.

FAQ (I've not actually been asked any quesitons :( but they're questions I'd ask, so I'm counting them):
Q: Uh oh, AliExpress! How long do these take to ship?!
A: The boards took about 1.5 weeks from order to arrive - CN -> UK.

Q: Will I have to unplug the USB cable from my tracker to charge both when flat?
A: No, you can plug in only the pucks USB C power in and it will charge both the puck and tracker battery at the same time.

Q: The USB A and C ports look close together! Will I have to unplug the USB A cable to charge the puck?
A: No, probably not. Depends on your cable, though the average right angled cable will have no issues.

Q: My tracker turns off when I put it on the puck, but immediately turns back on when I take it off! What happened?
A: The nuts probably shorted pins 2 and 3, causing it to go into a fail safe mode. You havent damaged the tracker in any way, so dont worry! This is most likely a spacing issue with either design or using too large a nut. I havent had the time to figure it out myself yet.

I'll make a V2 with multiple small batteries to reduce size one day, maybe if the size of these get on my nerves.

TODOs:

• Bevel edges to not be pointy, they hurt on my small feet after a while :(
• Make it harder for fixing nuts to fall out while screwing in.
• Make it so pogo pin nuts cant fall out while upside down
• Adjust height of haptic motor to let tracker sit more flush
• Adjust size of base screw holes to allow a standard 6mm screw bit to fit inside instead of the Xiaomi 4mm bit.
• Adjudt height of the screw mount a minor amount to reduce 20mm screw end poking out the top.
• Add Tundra support (USB only)
• Add Etee support (USB only)

For the lid, please print with supports as bed/base only, otherwise the supports can be hard to remove from the holes for the haptic motor, especially if printed at a high resolution.