Re drooping under load, yes they will, but they will bounce back up again when LEDs are off. Upside is Cr2032 cells will probably not drive enough current to destroy much. What I would question is how long those Cr2032s will run for?
Suggest having a look in the data sheet and measuring likely current before committing too much here. They can run a single LED for a couple of days but trying to make addressable LEDs run from them will be a big ask. They are designed to run for years under micro amp loads, not milliamps for a couple of hours so have a high internal resistance under load and much lower practical capacity.
Good question, I've read on the package these 2032's have 230mah, so together (electronics naivety kicking back) I'm guessing they would be 460mah together, they have Maxwell written on the package, I don't think they are the same cheap unbranded one's from aliexpress, so I would guess their rating is somewhat correct.
Whether 460mah will run even for an hour is another question. I'm using 20LEDs (3535 package), the WS2812's are advised 60ma per led (although I only use those rainbow modes), so anywhere from 20-60ma per led, 60 x 20 is 1.2A damn, but I guessed they current would be around half of that, so 0.5/0.6A or around an hour of play time with CR2032's is what I expected. And also I don't think the 3535 package has as much current draw as the 5050 led packages, but I stand to be corrected and usually just use the guidance for the 5050 RGB's.
If this is a once off prop it's fine but would suggest going to directly drive LEDs, in smaller numbers. The Teensy and prop shield sensors should be OK on the 3.3V regulated.
Possibly a better form factor for glasses is the batteries and chargers used for vaping. They are long and skinny and while theoretical capacity per gram or per cubic centimeter will be lower gives you more options.
I don't think it will be a one off prop, I would love to sell them (way) down the line, or open source the design (hope/prey it goes viral) and try and wrangle a job out it! Or at least make a few for my mates as I could only get the eyeglass hinges in packs of x5, so I have a few spares needing some purpose.
In regards to driving LEDs in smaller numbers, so there's one strip at the top, I don't know if it seems like they are brighter than just 20leds, but does powering 20 at a time seem reasonable to power?
When you say long skinny vape battery, (excuse my ignorance) but all I'm thinking of is those 18650 li-on batteries, unless you're thinking of a different form factor to the one I am. A vape battery would be perfect way to power them, they'll probably have way more ooompf than the CR2032 and have the benefit of being rechargeable.
Having seen your video, nice work! and changes some of my internal pictures that had a ring of glitter lights, not a light wall.
I have a tie with 4*13 LED matrix running up it that would go well with them.
You really do need to measure the current draw on that, a random google found this discussion
https://electronics.stackexchange.c...esting-chinese-cr2032-li-ion-battery-capacity
And there is also the write up at
https://www.evilmadscientist.com/2009/some-thoughts-on-throwies/
While you can still use CR2032 suspect you will need a complex serial/parallel mix to get the lifetime/voltage right and accept things getting weird as the flatten.
Also with using batteries in series, the fact that you have different voltages suggest you have batteries with different total capacities and you will only be able to draw down to the lesser of the pair, which is one reason why things like phones often boost a single big cell rather than dropping from a pair, because it allows them to optimise for that single cell, not the worst charge/discharge performance of two or more. Battery power is a complex world if you are doing it right.
Thank you for watching and the kind words! I think I know what your first mental image looked like, I've seen a few steam punk-y design's with a neopixel ring on the eye brims, they look cool, but I just love the diffusion effect where all the beams merge into one, so I sacrificed being able to see out of them in favour of coolness!
haha your tie would be a perfect add on, I'd like to see if you've got a picture knocking around! I'm sure this forum could set some sort of record with most amount of amps drawn from a wearable technology outfit! Side note I would see that fashion show!
I'm gonna take your advice and move away from trying to use the CR2032's, at £0.50-£1.00 per battery, and two lasting for est 1hour, it's not a very cost effective design as well. 24 hours of use est £24-£48 is more than the price of components for the glasses!
I agree whole heartedly with that last sentiment, "Battery power is a complex world if you are doing it right." two weeks ago I thought I could just put a rechargeable battery straight into the circuit without any hassle, didn't know anything about overcharge and you kill them, under charge and you kill them, and seem to be way above the rating when fully charged, eg 3.7 lipo's come out at 4.2 and then go back down to 3.7 for 80% of the time then drop. If I'm honest experimenting with disposables was a way of trying to negate the recharge headache, I realise now either way (rechargeable/dispose) you have to have the same considerations, what if voltage goes over mcu opeating voltages, what if it drops way below operating voltages.