DIY USB battery charger for cell phone Lithium ion batteries from a wireless mouse charger

This a great way to charge up cell phone batteries without a cell phone, most cell phone AC adapters will not charge a battery efficiently as they are around 5 volts DC the phone itself has the battery charger inside of it. But I find these batteries have allot of uses around the home or man cave. This Mouse charger is for a Logitech MX Revolution wireless mouse. Which uses a Lithium ion battery.


I claim to be no expert I would not try to charge the mouse and cell battery at the same time. However this setup has worked great for me for recharging these old batteries. I have 1 of these batteries powering my keyboard for the last 30 days and only lost 1 bar of power, I got about 18 hours of power for the brass horse lamp before recharging. And keep in mind that these batteries are not new.
Happy Charging! 

FOR SAFETY REASONS I SUGGEST YOU DON'T ATTEMPT TO DO THIS! UNLESS YOU KNOW AND UNDERSTAND BATTERIES AND BATTERY TYPES ALONG WITH CHARGERS AS I AM BY FAR NO EXPERT AND KNOW JUST ABOUT ENOUGH TO BE DANGEROUS. 

Step 1: Tools & Parts

Tools:

Soldering Iron
Solder & Flux
Wire Strippers 
Black Tape

Parts:

3.7 Volt Cell phone battery
USB Cable with male & female ends

Comments

[ironsmiter]

Does the original mouse still charge on this when you were done?
Presumably NOT with your "usb battery" attached, but when detached, it LOOKS like the normal operation should be unaffected.


Minor, but IMPORTANT note...
this works only with mice that use li-po batteries, like that particular logitech the author listed.

I give the warning on account of the fact that all the re-chargable wireless mice I personally have, use NiCd or NiMh, and those chargers will do very bad things to a LiPo cell phone battery. VERY bad things.

Second warning...
Though USB is VERY convenient as a connector...
I'd be very VERY worried that someone would come along, and plug that battery straight into a computer usb socket to recharge. Since the cellphone batteries have built-in protection circuits, it would probably not be a major disaster... but it likely WOULD kill the battery.

Dunno what would be BETTER, but the "paranoid about other people's stupidity fairy" tells me it's just not sound practice.

[VadimS]

Cell phone LiPo cells have vary limited protection, usually just overheat.
Most USB ports are current limited, so if plugged in for a short time it will do no harm, but if left plugged in or plugged into a non limited port (like USB3 or some cheap expansion cards) you will kill the battery.

[seawee65]

Erm... I'm a beginner at this, so you can't use a computer to charge it because the voltage it to high???

[Grasshopper1221]

The computer is not a LiPo charger.
If you plug it into your PC it may do very bad things to the battery and or USB port.
I would advise for you not to do this untill you have a better understanding of chargers & battery & types... less you burn some thing down.

[seawee65]

Oh... Thanks.

[Grasshopper1221]

I don't want to discourage you... All I am saying is get some basic knowledge of batteries and types of batteries along with charging systems as there are many types of batteries & charging systems.

I have little knowledge myself and know about enough to be dangerous.

[HealzNDealz]

Hahaha. Yes be very alert, there are MANY "stupidity fairies" on the internet.

[electfire]

Must say I love your little blurb of "...AND KNOW JUST ABOUT ENOUGH TO BE DANGEROUS." Reminds me of part of my own personal saying "...I know more than enough to be dangerous..."

I must say @ironsmiter has a good point about others stupidity... most people assume when they see a USB cable that the device can be connected to the computer.... I know USB connectors make a very handy connector, but I am wondering why you used USB.... was it just what you had on hand? Personally I would have either used a barrel-type jack, TRS jack (typ. headphone type jack), or a RJ-45 (think CAT-5 (Ethernet) or Telephone jack)

[Grasshopper1221]

Well I have a ton of USB cables and and rather toss them in the scrap pile they getting used up. The connectors were easy and on hand.

And as far as other people stupidity I can't argue with that.... However I believe that most people who may do this would not like other folks going through there Lab and messing with the natural order of things.

[Winged Fist]

Grasshopper – Another great instructable! You should consider expanding this instructable (or creating a new one) to include new uses for an old cell phone battery, like powering an Antique carousel Brass Horse Lamp;-)

I'm sure many Instructables regulars have aplenty of old cell phone batteries lying around, and if they're like me, it never occurred to them that these old batteries could be adapted with a usb plug to power new inventions!

Also a great way to keep these toxic little bricks out of the waste stream!;-)

Well done!

[Grasshopper1221]

Hello Ironsmiter:
Yes my mouse will still charge using this charger. And as I stated I am no expert on this subject I do know that my mouse uses a Lithium ion battery so that is why I chose to to use this charger for this. I would not try to charge both at the same time.

There would be nobody in my mancave to plug theses batteries into any PC USB port.