**Bike lights... never buying Duracell again...**
As a keen cyclist who often has to use bike lights during dangerous times like 2-3-4 AM due to night shift work, I was always interested in having my lights doubled for security reasons (besides the e-bike's own light, I also depended on another light on the bike and/or my backpack). Good quality (bright) lights are expensive, and when combined with quality batteries like Duracell (AAA, AA, or 2032), it really adds up. Plus, using them for longer periods means dealing with dimming batteries.
So, I converted my bike lights to USB using 18650 batteries or power packs with 10,000/20,000 mAh of juice. The usual LED bike lights work with 3V, 4.5V AAA/AA/2032 batteries, while my packs have an output of about 3.8 to 5V. The LEDs in the lights don’t mind this over-voltage (so far, not one bike light has stopped working in several years, even though some lights were only £5 but very suitable for their design and purpose) usage is month and month and month - the packs have a status light and constantly 5V output... my DIY packs have more Volt when empty (3,7V) than with full normal Batteries (3 or 3,5V)
To convert them, I use my old USB cables, which have only four wires. I only use the red (+) and black (-) wires, cutting off the other two. The USB plug is used, and the other end with mini, micro, or C is just cut off and stripped. I solder the red and black ends onto the battery terminals. Obviously, a small hole needs to be drilled into the casing to keep everything clean and tidy. I often glue the plastic cover to the case so it doesn’t open, which sometimes happened when using batteries.
USB cables come in any length (up to 5m) and any color, even “clear,” and are mostly free since everyone has redundant cables lying around at home. Old power packs that aren’t “strong” enough for IT use work too. The 18650 lithium batteries are old e-bike cells or from old laptop batteries. Often, they are already spot-welded in parallel (2 or 3), making it easy to solder a USB socket (or cable end from a USB extension) onto the pack. The pack itself can be charged in a normal 1-18650 charging adapter from an old e-cigarette charger or torch.
As a keen cyclist who often has to use bike lights during dangerous times like 2-3-4 AM due to night shift work, I was always interested in having my lights doubled for security reasons (besides the e-bike's own light, I also depended on another light on the bike and/or my backpack). Good quality (bright) lights are expensive, and when combined with quality batteries like Duracell (AAA, AA, or 2032), it really adds up. Plus, using them for longer periods means dealing with dimming batteries.
So, I converted my bike lights to USB using 18650 batteries or power packs with 10,000/20,000 mAh of juice. The usual LED bike lights work with 3V, 4.5V AAA/AA/2032 batteries, while my packs have an output of about 3.8 to 5V. The LEDs in the lights don’t mind this over-voltage (so far, not one bike light has stopped working in several years, even though some lights were only £5 but very suitable for their design and purpose) usage is month and month and month - the packs have a status light and constantly 5V output... my DIY packs have more Volt when empty (3,7V) than with full normal Batteries (3 or 3,5V)
To convert them, I use my old USB cables, which have only four wires. I only use the red (+) and black (-) wires, cutting off the other two. The USB plug is used, and the other end with mini, micro, or C is just cut off and stripped. I solder the red and black ends onto the battery terminals. Obviously, a small hole needs to be drilled into the casing to keep everything clean and tidy. I often glue the plastic cover to the case so it doesn’t open, which sometimes happened when using batteries.
USB cables come in any length (up to 5m) and any color, even “clear,” and are mostly free since everyone has redundant cables lying around at home. Old power packs that aren’t “strong” enough for IT use work too. The 18650 lithium batteries are old e-bike cells or from old laptop batteries. Often, they are already spot-welded in parallel (2 or 3), making it easy to solder a USB socket (or cable end from a USB extension) onto the pack. The pack itself can be charged in a normal 1-18650 charging adapter from an old e-cigarette charger or torch.
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