Davebait 3 - The everlasting battery ? - Page 1
Forum section: electronics / general

author: PinheadBE
author_rank: Regular Contributor
timestamp: January 13, 2018, 12:20:33 pm
content: I disclaim all side effects that this article could have on Dave's health, nor take any responsability into the rant storm that could flood the youtube channel in the coming centuriesHere's one that is worth the reading :https://gizmodo.com/this-aa-battery-sucks-power-right-out-of-the-air-1821966213So, what's your opinion ?or?

author: Rerouter
author_rank: Super Contributor
timestamp: January 13, 2018, 12:27:54 pm
content: There example of using it in a remote is probably a fair use case, it would have a capacitor and a regualtor inside it, so by blowing out probably 10W of radiated power i could easily forsee it covering some channel surfing,The biggest issue relates to why people use batteries, generally you battery power a device because you don't want it to be locked to 1 location, e.g. you go out on your porch but want the TV on showing a game of sport, well you have just gained 8 meters away from the transmitter, and it may begin copping out over that distance.The IOT devices they hint at, honestly there are very few times where i expect something to be both wifi enabled, and battery powered.

author: PinheadBE
author_rank: Regular Contributor
timestamp: January 13, 2018, 12:51:12 pm
content: Let's consider we use this without the power hungry transmitter (yes: what about efficiency ?).They claim that the battery would also load itself with the ambiant RF waves (isn't it ?). I wonder what power could effictively be retrieved that way.

author: Rerouter
author_rank: Super Contributor
timestamp: January 13, 2018, 01:00:58 pm
content: ambient radio waves... unless your in a cafe in the center of the city, your looking at micro-watts to possibly milliwatts, there antenna is tiny to fit in an AA casing, its likely obstructed by the PCB that the battery holder is over, etc,Linear tech has plenty of ambient RF grabbing demo boards if you want a real world example, but for most devices its not really going to work,Part of me forsees someone trying it out in a fire alarm because lets face it no one likes changing the battery in them each year, wonder what the legal process would be there, a powercut making a reliable device disabled.

author: tszaboo
author_rank: Super Contributor
timestamp: January 13, 2018, 01:25:12 pm
content: It is totally worth spending 100 EUR+ on a device to avoid replacing a couple of 0.3 EUR batteries every half decade.

author: nanofrog
author_rank: Super Contributor
timestamp: January 13, 2018, 02:43:09 pm
content: Way too expensive for remote control batteries.And in the case of smart phones (and presumably other devices over time), there are already established and far less expensive ways to make a device induction charger capable. Heck, it's even easily added to older smart phones (just add the coil).I do see it as a better solution on a commercial/industrial scale than the current methodology though, as a single charger eliminates the need for 1 device per charger on a large scale. It would also allow users to keep their device/s on their person (true mobility). Assuming it genuinely will work once it's out in the wild of course.

author: PinheadBE
author_rank: Regular Contributor
timestamp: January 13, 2018, 03:01:51 pm
content: I would give an arm to see Dave make the maths

author: paulca
author_rank: Super Contributor
timestamp: February 21, 2018, 07:45:08 am
content: There are such things as ever lasting batteries. Ever owned a Casio watch or calculator? (tehe)

author: ogden
author_rank: Super Contributor
timestamp: February 21, 2018, 10:03:14 am
content: Oh, geezThis is basically microwave oven steering it's energy all over the place.Some excerpts oftheir specs:Freq = 2.8 GHzrange up-to 30ft8W radiated for 1W deliveredBest part:"To operate within the FCC’s (Federal Communications Commission’s) safety standards the rate of power transmission is one-third to one-fifth of standard USB charge speed"To charge iPhone, 18 hours are neededAntennas are not ideal. They do not radiate "RF lasers". Sidelobes exist no matter how good antenna is.Beamforming is no different. So while your phone is charging, some sidelobe can be frying your eyeball as well... Or just saturating LNA of WiFi deice you are using rendering it useless during "wireless charge"

author: PinheadBE
author_rank: Regular Contributor
timestamp: February 21, 2018, 05:07:07 pm
content: Quote from: paulca on February 21, 2018, 07:45:08 amPoint taken !Those beasts were well ahead of their time in terms of energy savings !Quote from: ogden on February 21, 2018, 10:03:14 amYES ! Come on, come on.... Dave's not far away

author: PinheadBE
author_rank: Regular Contributor
timestamp: February 21, 2018, 06:08:18 pm
content: Will this charge my cell phone ?1°) This faint energy does NOT come out of nowhere2°) It is so faint that it could also be only some variations in Earth's magnetic field, or the movement could be produced by subtle tectonic movesBut, we are order of magnitudes away from charging a cell phone, aren't we ?

author: glarsson
author_rank: Frequent Contributor
timestamp: February 21, 2018, 06:19:33 pm
content: Quote from: paulca on February 21, 2018, 07:45:08 amThe battery in my old Minolta SRT101 was replaced sometime in the second half of the seventies. Now 40 years later the 1.35V PX625 battery still works, just like when it was new. These batteries were so good they had to be banned.

author: Red Squirrel
author_rank: Super Contributor
timestamp: February 21, 2018, 08:40:45 pm
content: One of these days Dave is going to get an aneurysm on camera from these BS inventions.Also what is with this obsession of wireless electricity, is it really that hard to plug something in? Any form of wireless electricity that would be usable would probably have lot of health risks.Wireless is probably the #1 buzzword of this century.

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 24, 2018, 05:05:07 pm
content: Very funny indeed.Especially since wireless transmission of energy has been studied and done extensively by resonant inductive coupling.Doing the same with RF, just because it looks hype, seems not only stupid (unless it's aimed at ultra-low power, such as with UHF RFID, which has its uses) and inefficient, but also forms a health hazard and has a rather low chance of getting regulatory approved.

author: Kontakr
author_rank: Contributor
timestamp: February 27, 2018, 02:02:57 am
content: 12.5% power delivered? I want to know what range they were at to hit that high of an efficiency.