Lifecraft
John McDouall Stuart
A while ago I got one of these off ebay:

It's a handy little gadget. 9/10 times when I need a light in the dark something like this is sufficient, even though it's not as powerful as a torch.
Unfortunately it's not rechargable, so I don't want to use it regularly (as I don't want to buy batteries if I can avoid it).
So I decided to create a rechargable version I can charge from my portable hiking solar panel.
It's ugly, but it works:



I included the AAA battery in the photo for scale (but no it's not running off an AAA battery).
There's a button switch on the top. A smaller one might have been better but it's the only suitable one I had.
I coated the entire thing in hot glue to insulate the electronics. The only parts exposed are the LED, switch, and USB charging port. I could have done a neater job of that but it doesn't effect how it works.
You can see the red glow indicating it's charging. It switches to blue once it's charged. (That's all built into the charging module.)
It weighs 14 grams according to my kitchen scales. To put that into perspective, the AAA battery in the photo is 11 grams.
It's so light partly because the battery I used is a cheap RC helicopter battery, which is obviously designed to be light.
The whole thing would have cost less than $5 in parts:
- 240mah lipo battery
- lipo charging module
- led
- resistor
- switch
- wire
It's a really simple project that doesn't need any special skills or experience. Even a complete beginner should be able to make it as long as you're prepared to do a little bit of soldering and hot gluing. (You can tell that I'm a novice with the hot glue gun just by looking at it).
If you'd like to have a go at it let me know and I'll post links to the parts (on ebay and/or aliexpress because it's cheap) as well as some diagrams for how to wire it up.
You can use the exact same approach to make USB battery packs and various other rechargable gadgets too. Just swap out the LED for whatever you want. For a USB battery pack just swap it for a 5v boost regulator with a USB socket.
It's also fairly easy to attach small solar panels to the charging module to make gadgets solar powered without an external panel. I used that approach (and same battery/charging module) to make a solar night light (I'm yet to make a post about that).
Once I do a test to see how long the battery lasts I'll post an update.
The specs should be similar to that of an LED throwie because the battery the same as a CR2032 battery used in LED throwies.
Does anyone have any ideas about how to add a lanyard or keychain? Maybe I should have attached that under the layers of hot glue.
I want it to be convenient enough to keep in my pocket or in my pack without losing it.

It's a handy little gadget. 9/10 times when I need a light in the dark something like this is sufficient, even though it's not as powerful as a torch.
Unfortunately it's not rechargable, so I don't want to use it regularly (as I don't want to buy batteries if I can avoid it).
So I decided to create a rechargable version I can charge from my portable hiking solar panel.
It's ugly, but it works:



I included the AAA battery in the photo for scale (but no it's not running off an AAA battery).
There's a button switch on the top. A smaller one might have been better but it's the only suitable one I had.
I coated the entire thing in hot glue to insulate the electronics. The only parts exposed are the LED, switch, and USB charging port. I could have done a neater job of that but it doesn't effect how it works.
You can see the red glow indicating it's charging. It switches to blue once it's charged. (That's all built into the charging module.)
It weighs 14 grams according to my kitchen scales. To put that into perspective, the AAA battery in the photo is 11 grams.
It's so light partly because the battery I used is a cheap RC helicopter battery, which is obviously designed to be light.
The whole thing would have cost less than $5 in parts:
- 240mah lipo battery
- lipo charging module
- led
- resistor
- switch
- wire
It's a really simple project that doesn't need any special skills or experience. Even a complete beginner should be able to make it as long as you're prepared to do a little bit of soldering and hot gluing. (You can tell that I'm a novice with the hot glue gun just by looking at it).
If you'd like to have a go at it let me know and I'll post links to the parts (on ebay and/or aliexpress because it's cheap) as well as some diagrams for how to wire it up.
You can use the exact same approach to make USB battery packs and various other rechargable gadgets too. Just swap out the LED for whatever you want. For a USB battery pack just swap it for a 5v boost regulator with a USB socket.
It's also fairly easy to attach small solar panels to the charging module to make gadgets solar powered without an external panel. I used that approach (and same battery/charging module) to make a solar night light (I'm yet to make a post about that).
Once I do a test to see how long the battery lasts I'll post an update.
The specs should be similar to that of an LED throwie because the battery the same as a CR2032 battery used in LED throwies.
Does anyone have any ideas about how to add a lanyard or keychain? Maybe I should have attached that under the layers of hot glue.
I want it to be convenient enough to keep in my pocket or in my pack without losing it.
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