There are many "9V" battery chargers currently on the market, but sadly most of them are just "dumb" chargers that simply provide a current-limited supply at a fixed voltage to the battery, and it's rare to find a professional charger that can properly charge a PP3 rechargeable battery.

Most of these issues stem from the fact that there are way too many PP3 rechargeable battery types on the market that go from 7.2V up to 9.6V, not only that but we even have different chemistries of batteries with the majority being NiMH, but currently, a lot of people are opting for LiIon alternatives that recently came to market at affordable prices. This creates a lot of problems if you want to create a universal charger for all of these batteries.

All of these problems made us create this product with the intent of providing a one-stop solution to all your PP3 battery charging needs in a compact and convenient form-factor that allows you to charge any "9V" rechargeable battery that you might have directly from a standard USB port while fitting neatly inside an Altoids tin.

The charger can be powered from any regular USB port using a Micro-B cable and can charge any PP3 rechargeable battery currently available on the market. Not only that, but it's also able to discharge the batteries and also perform a full discharge/charge cycle using the refresh function, giving you a healthier battery, especially since most of these rechargeable PP3 batteries get abused by devices that usually over-discharge them and performing a full cycle on them some times restore a bit of capacity that might have been lost.

Circuit Board

					PCB Layout
Technical Details
Battery Chemistries NiMH and LiIon
LiIon Nominal Voltages 7.4V
NiMH Nominal Voltages 7.2V, 8.4V, 9.6V
Charge/Discharge Rates 15mA, 50mA, 75mA, 100mA
Max Current Consumption <500mA
Main Controller Microchip PIC16F18235
Populated Board
Populated Board

The board ready to be put inside an Altoids tin. You'll have to provide your own tin and drill it yourself.

Complete Unit
Complete Unit

The charger already inside an original Altoids tin. Sadly you won't get the mints that were originally inside.

Assembled board starting at:


Complete unit inside an original Altoids tin: $22.90
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