Comments on: EEVblog #55 – RCA Airnergy WiFi Hotspot Energy Harvesting Marketing BS

By: SomeMoreVideos2468

SomeMoreVideos2468 — Mon, 08 Feb 2010 12:04:57 +0000

Yeah the 15 minute charger was for NiMH which can be charged that fast but it’s a totally different chemistry. Li-ions would just explode if that much current was forced through them. Most Li-ion batteries have a maximum charge rate of C/3 but smaller ones like those used in mobiles can sometimes be charged at up to 1C. ATM there’s just no Li-ion batteries in production which could support such a high charge rate but even if there was – why not just use a charger for them??

By: SomeMoreVideos2468

SomeMoreVideos2468 — Mon, 08 Feb 2010 11:47:28 +0000

Oh and one more thing – I don’t have a slow charger – a C/3 charge rate for Li-ion batteries is a rapid charge. My point is that there really isn’t any point in charging something from a microwave as it would be expensive, inefficient and would probably just damage your microwave oven because of arcing since very little of the ~1kw of microwave energy would be picked up by the antenna. Supercaps are emerging which can be charged in a matter of seconds but my point still applies…

By: SomeMoreVideos2468

SomeMoreVideos2468 — Mon, 08 Feb 2010 11:40:59 +0000

Yeah and what confuses me about this is why would they tune it to 2.4GHz – why not just pick up all RF? I mean it still wouldn’t be enough to do much but it would be better than form just 1 frequency. You’d get more energy by sticking a solar panel to the back of it!
I wouldn’t like to have enough RF around to power a phone or something – your body is very effective at picking it up too!

By: Vlakpage

Vlakpage — Mon, 08 Feb 2010 10:54:23 +0000

@SomeMoreVideos2468 For example take a look at Toshiba’s SCiB. They claim 90% charge after 5 minutes at rate 12C or 90% after 10 mins at 5C. It should be available next year. Not targetted at mobile handheld devices though.

Li-Poly for RC models can be charged in about 1 hour and stays cool (I have one)

I don’t say it’d good to charge your phone in microwave oven, just that these fast charging batteries exist and there will be more in future. Li-based chemistry is still in heavy development.

By: SomeMoreVideos2468

SomeMoreVideos2468 — Mon, 08 Feb 2010 10:40:54 +0000

Oh yeah, for sure – my main point was I couldn’t see a microwave charger being useful. I was referring to currently available batteries when I was talking about charge rates. And as I said supercaps can be charged in a matter of seconds but aren’t mainstream yet.

By: pikuorguk

pikuorguk — Mon, 08 Feb 2010 09:45:08 +0000

I think the fillings in my teeth collect more energy from cosmic rays. I’m off to patent the idea so that in the future, when we work this out properly I can make loads of money

By: yoyomin

yoyomin — Mon, 08 Feb 2010 09:09:50 +0000

I guess that was MY idea :p

By: Flapjackbatter

Flapjackbatter — Mon, 08 Feb 2010 08:16:32 +0000

I did a quick websearch , and from comments on forums around the net you can see ppl bying into this bullshit.
Only about one or two in ca 10 comments are sceptical.
We`re surrounded by idiots !

By: supercannon2

supercannon2 — Mon, 08 Feb 2010 07:59:06 +0000

RCA is nothing but a label. Thomson Consumer Electronics is the corporation that own,s rca name and many other’s. I’ve had my run in’s with this outfit with their prduct’s before. Enjoy you’r informative vid’s Dave.

By: vaneenbergen

vaneenbergen — Mon, 08 Feb 2010 07:05:34 +0000

Why not use the unit together with your lunch in a microwave-oven Indeed complete BS. Dave great blog always waiting on the next one.