Search found 45 matches

by solar3000
Sat May 16, 2020 7:17 pm
Forum: General Discussion
Topic: Charging lithium ions
Replies: 2
Views: 204

Charging lithium ions

I have a stack of 18650 cells. Any charger I put them in will raise the voltage to 4.2 volts. That's great, but as we know, it will kill the cell at that voltage after a few months. Since I can't find a charger that will charge it to a lower voltage, say 3.7 or 3.8 volts. What do you think of a disc...
by solar3000
Sat May 16, 2020 7:07 pm
Forum: General Discussion
Topic: Is Nuts and Volts dead ?
Replies: 55
Views: 14413

Re: Is Nuts and Volts dead ?

Are we still trying to figure out if NV is dead?
Sad fact, but like it or not, it is fading slowly.
I remember when I was still reading Radio Electronics in cuneiform on clay tablets. Those were the days.
cuniform.jpg
by solar3000
Fri May 15, 2020 6:37 am
Forum: General Discussion
Topic: Superduper capacitor substitute for battery
Replies: 12
Views: 557

Re: Superduper capacitor substitute for battery

And, yes, I would love to replace battery packs, if possible, if practical.
by solar3000
Fri May 15, 2020 6:35 am
Forum: General Discussion
Topic: Superduper capacitor substitute for battery
Replies: 12
Views: 557

Re: Superduper capacitor substitute for battery

Sounds very doable. Just came in from Digikey: 45F 5.6 volt cap. It's the size of a 'n' cell, but slightly smaller. I charged it to about 4 volts and it powered an LED for a while. I didn't time it. The cap started heating up fast. Hey, why does it heat up like that? I connected a 1 watt white LED. ...
by solar3000
Sat May 09, 2020 8:22 am
Forum: General Discussion
Topic: Superduper capacitor substitute for battery
Replies: 12
Views: 557

Superduper capacitor substitute for battery

How about a superduper capacitor substitute for a battery? Let us hypothetically have a dual-AA battery powered lamp that runs for 30 minutes on 3 volts. And lets us replace the two AAs with some superduper capacitors. Now, lets make some slight adjustments. Super caps usually sell 2.5 volts caps. S...
by solar3000
Tue Jul 02, 2019 4:48 pm
Forum: General Discussion
Topic: Is Nuts and Volts dead ?
Replies: 55
Views: 14413

Re: Is Nuts and Volts dead ?

Wow this is sad. I remember when I was a boy. I used to read radio electronics. They used to sell it at all major book stores. It was a big deal when you wind your own coil for a shortwave transmitter. And the ages before that when building a radio receiver was something to be proud of. I remember w...
by solar3000
Wed May 29, 2019 4:56 pm
Forum: General Discussion
Topic: cutoff circuit for battery
Replies: 3
Views: 2407

cutoff circuit for battery

What's a simple circuit for low voltage cut-off?
I'm thinking of several circuits. One [li-ion] 3 volt low; 4 volt high. Another with a minimum of 12 volts.
by solar3000
Thu May 16, 2019 5:00 pm
Forum: General Discussion
Topic: Li-Po cell Id.
Replies: 13
Views: 2713

Re: Li-Po cell Id.

by solar3000
Fri May 10, 2019 6:47 pm
Forum: General Discussion
Topic: [18650] rechargeable battery + super capacitor
Replies: 7
Views: 2137

Re: [18650] rechargeable battery + super capacitor

what about this guy: a 45F 5.6 volt super duper capacitor. And how is it only $11USD?

https://www.digikey.com/product-detail/ ... ND/7318587
by solar3000
Fri May 10, 2019 4:15 pm
Forum: General Discussion
Topic: [18650] rechargeable battery + super capacitor
Replies: 7
Views: 2137

Re: [18650] rechargeable battery + super capacitor

Well, I'm thinking a super cap in parallel with the li ion battery, before the USB booster. So what's a li ion, 3 volts to 4 volts? And how long does it take to switch a battery? Perhaps 5 to 10 seconds? I'll stick to the high side of the drain, say 160 mA. I saw a super cap rated at 5v at 4F. Some ...
by solar3000
Thu May 09, 2019 9:47 pm
Forum: General Discussion
Topic: CNC Router anyone?
Replies: 5
Views: 1995

Re: CNC Router anyone?

....7 days later....
Hi friend. Its very lonely here.
I would love to have a CNC, but I have no space in my tiny apartment.
I need a bigger place to go with that CNC.
I would love to have a pick-and-place circuit board maker thing.
by solar3000
Thu May 09, 2019 9:44 pm
Forum: General Discussion
Topic: Is Nuts and Volts dead ?
Replies: 55
Views: 14413

Re: Is Nuts and Volts dead ?

I like my magazines carved on clay tablets.
by solar3000
Thu May 09, 2019 9:41 pm
Forum: General Discussion
Topic: [18650] rechargeable battery + super capacitor
Replies: 7
Views: 2137

[18650] rechargeable battery + super capacitor

I'm building a pocket project that I'm going to put in my pocket and walk around with. Inside is a battery and a 3.6v to 5 v boost. Also inside is a raspberry pi zero, but it could be any small electronics as well. When I need to change battery, I would have to shut down the load. I'm wondering if I...
by solar3000
Fri Oct 19, 2018 8:42 am
Forum: General Discussion
Topic: USB-C, 100 watts?
Replies: 2
Views: 798

USB-C, 100 watts?

I've been reading about how USB-C can transfer 100 watts. But no one seems to know how.
Not at five volts or else the copper would have to be an inch thick.