Off-the-Grid Forum - Recent Threads

The "Dead" Battery Lamp

scottiebabe — Sun, 11 Jun 2023 17:53:09 GMT

Soft 404

RE: The "Dead" Battery Lamp

DAB — Tue, 13 Jun 2023 20:24:37 GMT

I like it, I have dozens of half dead batteries lying around.

RE: The "Dead" Battery Lamp

cstanton — Tue, 13 Jun 2023 13:54:18 GMT

... I've been resisting this for years. Looks like they have really expanded their range!

RE: The "Dead" Battery Lamp

scottiebabe — Tue, 13 Jun 2023 00:47:18 GMT

Apparently flux capacitor chargers are real!

RE: The "Dead" Battery Lamp

robogary — Mon, 12 Jun 2023 20:43:31 GMT

I use this phone charger

RE: The "Dead" Battery Lamp

scottiebabe — Mon, 12 Jun 2023 17:06:23 GMT

Tinkering away on one of those!

I have thought about trying one of these:

Biolite

A small solar panel is much cheaper, but doesn't work well indoors or at night...

RE: The "Dead" Battery Lamp

beacon_dave — Mon, 12 Jun 2023 16:46:56 GMT

Only if you use it to power a LED lamp....

https://www.ecofan.co.uk/joi-lamp.html

RE: The "Dead" Battery Lamp

beacon_dave — Mon, 12 Jun 2023 16:41:44 GMT

field sobriety test - if you can open it, read the IC number and explain how it works, you are good for a couple more...

RE: The "Dead" Battery Lamp

cstanton — Mon, 12 Jun 2023 14:52:34 GMT

Oof tea light candles, perfect for burning a hole in your surfaces!

RE: The "Dead" Battery Lamp

scottiebabe — Mon, 12 Jun 2023 14:40:18 GMT

You can get a 100 pack for a few dollars

But you can also watch your money burn with a soy oil, natural essential oil candle as well.

But assuming you're prepared an LED anything is so much brighter than a candle lol

RE: The "Dead" Battery Lamp

cstanton — Mon, 12 Jun 2023 14:13:45 GMT

I found it really difficult to find plain candles for this purpose...

RE: The "Dead" Battery Lamp

scottiebabe — Mon, 12 Jun 2023 14:12:41 GMT

Of course no one would ever consider lighting a candle when the powers out 🕯

RE: The "Dead" Battery Lamp

scottiebabe — Mon, 12 Jun 2023 14:10:27 GMT

Thanks, I could measure the battery life of a lemon battery with my USB tester... thinking of it!

RE: The "Dead" Battery Lamp

scottiebabe — Mon, 12 Jun 2023 14:05:07 GMT

Element14 Members are the best!

RE: The "Dead" Battery Lamp

Jan Cumps — Mon, 12 Jun 2023 12:25:23 GMT

Are you telling us that you poke open those clips when you go out? That's a very high nerd factor 🙂

RE: The "Dead" Battery Lamp

robogary — Mon, 12 Jun 2023 00:26:25 GMT

Nice idea. Maybe can boost it to 1.3v and squeeze that lemon into a rechargeable battery. Wii controllers make alot of lemon squeezes

RE: The "Dead" Battery Lamp

beacon_dave — Sun, 11 Jun 2023 20:09:50 GMT

It's probably powered a few Rudolf's noses over the years at Xmas. Used to see similar on the back of beer pump clips in bars for seasonal promotions.

RE: The "Dead" Battery Lamp

beacon_dave — Sun, 11 Jun 2023 20:05:49 GMT

Have you tried wind generators yet ?

https://www.instructables.com/WINTURER-a-Portable-NP-F-Battery-Charger-Wind-Turb/

RE: The "Dead" Battery Lamp

Jan Cumps — Sun, 11 Jun 2023 19:46:14 GMT

[quote userid="395267" url="~/challenges-projects/project14/off-the-grid/f/off-the-grid-forum/53106/the-dead-battery-lamp/210364"]on such power budgets[/quote]

"the sniff of an oily rag"

RE: The "Dead" Battery Lamp

scottiebabe — Sun, 11 Jun 2023 19:36:06 GMT

Every mW counts! Dave Jones claims you can fly to the moon on such power budgets 🙂

Time to stock up on 5V solar panels just in case: Checkout this test rig

RE: The "Dead" Battery Lamp

scottiebabe — Sun, 11 Jun 2023 19:32:32 GMT

It took me a minute to remember this part, the LM3909 single cell flasher:

It only runs down to maybe 1V in practice, I don't know its been ages since I have seen one or used one....

RE: The "Dead" Battery Lamp

beacon_dave — Sun, 11 Jun 2023 19:24:35 GMT

A simple module like that could be used to charge a basic USB powered device like a power bank from an alkaline cell in pretty much any state of discharge. Handy when you are off grid and nowhere to plug a USB charger into. In the ol' days you used to be able to swap your NiCd AA rechargeable cells with a pack of alkalines from the nearest store. Harder to do that these days with this new-fangled stuff.

RE: The "Dead" Battery Lamp

scottiebabe — Sun, 11 Jun 2023 18:58:46 GMT

Yes, past 600 mV there isn't much left... Of course you can use a fresh cell too 🙂

Some of the low cost dollar store solar lamps use tabbed ni-mh cells, I'm sure if I were to shop around I could find them for pennies...

RE: The "Dead" Battery Lamp

Jan Cumps — Sun, 11 Jun 2023 18:23:43 GMT

you could, but for a very short time. By the time an alkaline battery has dropped to that voltage, there's virtually no joules left.

RE: The "Dead" Battery Lamp

scottiebabe — Sun, 11 Jun 2023 18:20:16 GMT

Excellent reference! Karen did a wonderful job on her joule-thief circuit. I thought about mentioning it, takes for mentioning Karen's project!

These modules are beginner friendly and provide a regulated stable DC output. So you could also run a neopixel and small mcu off a single alkaline cell.