Phone-charging belt with flexible batteries - Page 1
Forum section: electronics / general

author: polar8
author_rank: Contributor
timestamp: November 26, 2014, 02:04:39 am
content: https://www.indiegogo.com/projects/xoo-belt-by-nifty-a-phone-charging-beltAny idea what kind of battery they're demonstrating?

author: polar8
author_rank: Contributor
timestamp: November 26, 2014, 02:07:37 am
content: Demonstration of the lipo:

author: miguelvp
author_rank: Super Contributor
timestamp: November 26, 2014, 03:42:20 am
content: Audio is annoying to the point I had to stop watching that video.

author: johansen
author_rank: Super Contributor
timestamp: November 26, 2014, 05:38:20 am
content: and what happens when it catches on fire..

author: ConKbot
author_rank: Super Contributor
timestamp: November 26, 2014, 12:25:13 pm
content: http://www.powerstream.com/thin-lithium-ion.htmIn the 0.6mm thickness, looks like they get 2.17 mAH/cm^2. So ~3.5 cm wide by ~70 cm of usable space in a belt that isnt going to get pinched in the latch, 85cm or more if they have a latch which grips the edge or something where it wont damage the battery. Works out to 531 mAh/layer for the short battery, 645mAh/layer for a thicker battery. So call that 4 layers to reach 2100mAh either way, 2.4mm thick of battery, 2mm of leather either side makes for a 6mm thick belt. kind of beefy, but Ive seen stuff around that.4 layers would slide over each other as you bend it, and be better than one 2.4mm thick battery. So, plausible claims, not totally far fetched.

author: wraper
author_rank: Unknown
timestamp: November 26, 2014, 12:31:10 pm
content: Quote from: johansen on November 26, 2014, 05:38:20 am

author: ConKbot
author_rank: Super Contributor
timestamp: November 26, 2014, 05:24:06 pm
content: Its missing his pants being around his ankles because the belt went up in flames

author: mikerj
author_rank: Super Contributor
timestamp: November 28, 2014, 01:05:48 pm
content: Quote from: johansen on November 26, 2014, 05:38:20 amhad one of these belts.

author: Refrigerator
author_rank: Super Contributor
timestamp: November 28, 2014, 04:08:54 pm
content: Come on guys, people are trying to innovate.

author: rob77
author_rank: Super Contributor
timestamp: November 28, 2014, 05:15:14 pm
content: i would rather prefer a charger built into a backpack than into my beltif my backpack catches fire , then i'll simply drop it... but if the belt catches fire.... well.... i could imagine a better day

author: PlainName
author_rank: Super Contributor
timestamp: November 30, 2014, 12:38:10 am
content: QuoteAnd yet many people - possibly even you - are happy to shove their phone in the front pocket of their jeans without a second thought.

author: rob77
author_rank: Super Contributor
timestamp: November 30, 2014, 01:55:47 am
content: Quote from: dunkemhigh on November 30, 2014, 12:38:10 amthe phone and it's lithium battery are rigid and the current draw is minimal when the phone is in my pocket... so the risk of catching fire is practically zero... the batteries like to catch fire either during charging, heavy discharging or during mechanical stress/damage.ok the guys demonstrated the cells are pretty durable - punctured and cut the cell several times in the video.... but they didn't demonstrate the many thousand times bendingand actually that's what happening to a belt during wearing - constant bending during the day... it's not a "single bend" in the morning and then static all day.... it's thousands of changes in the curvature of the bend all day long.

author: PlainName
author_rank: Super Contributor
timestamp: November 30, 2014, 11:34:51 am
content: QuoteNot quite zero - it has happened more than once. There is some thought that these instances were due to after market batteries, but that's irrelevant to the point that those people shoved their phones down their pants.More relevant, I would have thought, is that this IGG affair would carry the appropriate test marks (whereas the 'light-up' batteries above probably didn't). As such they would be as safe as original batteries - otherwise they wouldn't pass the tests - so no more likely to burst into flames. If thedon'tpass those tests then you a) know you're buying rubbish and/or b) they wouldn't be able to complete the project. Either way, if the batteries are a liability they would be in reallyreallydeep shit.I wouldn't worry that the batteries fail catastrophically. I would worry that my money disappears because they can't ship safe batteries.Incidentally, BBC Click! showed this project over the weekend. They (Click!) tend to be near the bleeding edge but generally don't show hopeless stuff that doesn't have a chance. Not sure if that means anything regarding this project - maybe they got hoodwinked, or they have new and more gullible researchers just joined

author: rob77
author_rank: Super Contributor
timestamp: November 30, 2014, 04:59:01 pm
content: Quote from: dunkemhigh on November 30, 2014, 11:34:51 amagree it's definitely not zero - but the very few cases per many many millions of batteries is "practically zero".it's like aviation - the chances that the plane you're travelling on will crash is practically zero, but we all know plane crashes do happen sometimes.so in fact we can consider the rigid phone battery safe (as travelling via airplanes is the safest way of transportation) under the standard circumstances (no overload, no damage from mechanical stress).