EEVblog Electronics Community Forum

EEVblog => EEVblog Specific => Topic started by: TheWelly888 on July 04, 2010, 06:10:56 pm

Title: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: TheWelly888 on July 04, 2010, 06:10:56 pm
I rather doubt this patent of M$ will take the world by storm, battery sizes are only nominal with quite wide dimensional tolerances so a springless battery holder will only work when the batteries are exactly the right dimensions! Hang on.... perhaps M$ are planning to produce and sell exclusively batteries of exactly the right specs to fit their patented holders... :-\

Love your T shirt! ;D Last time anyone ever heard positive feedback from me was the sound of my hearing aid whistling!
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: allanw on July 04, 2010, 07:24:15 pm
nipple
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 04, 2010, 08:27:45 pm
Interesting.  The main item is just the connector, and its fairly simple, which makes it likely to work.

The key thing is can it withstand shock and vibration, and it hinges on battery's maintaining the proper dimensions when it comes to the + / - terminal specs.

There are 2 variants.  I like the lower one.  When you insert a battery, the long + nose contacts the deeper terminal, while the flat bottom - contacts the outer terminal.  It also seems to be angled to push forward like a spring. 

In the upper variant, inserting the battery momentary connects the + with the - terminal.

In both variants, you could have a nonconductive spring behind the assembly, pushing forward to engage the batteries.

http://download.microsoft.com/download/3/8/D/38D13CF1-F634-43B3-9189-16D7D6943635/Microsoft_InstaLoad_Brochure.pdf

Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: EEVblog on July 05, 2010, 02:07:16 am
I've submitted this to Slashdot:
http://slashdot.org/submission/1274938/Microsofts-Instaload-Battery-Technology-Patent?art_pos=1

So anyone in a position to "vote it up" it would be much appreciated!

Thanks.
Dave.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: allanw on July 05, 2010, 02:09:59 am
Seems like something Slashdot would like. The submission doesn't seem to be in the format that Slashdot stories typically are though, so that'd hurt your chances.

I'll submit it to reddit.com's r/electronics (http://www.reddit.com/r/electronics) too.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: ProfK on July 05, 2010, 05:02:40 am
Even the best of battery brands I have seen bloat and distort as they leak after a year or so of being installed in a device.  Often even after leaking I measure a voltage on the cell.  So a bad cell is not dead. I cannot help thinking the leakage of the cell that often is only at one end, wouldn't short across these two poles and cause heating or burning or worse. Practical design concepts with batteries are that the terminals of opposite polarity on a battery not be brought close to each other in order to avoid accidents.  9V batteries are fine examples. Keep a 9V in your pocket with change or keys and you start a fire.
I can't help thinking how poor a design this is. This can only add cost to the battery and the devices. Rack it up to new and improved sales hype. 
What of the series stacking of 1.5 V cells? The wiring alone is costly to equipment manufacturers on the assembly line. The battery compartment will need to be machine produced because the days of hand wiring the connections will be gone if this battery catches on. 
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: Ferroto on July 05, 2010, 01:58:18 pm
Microsoft's problem has always been sticking with it's knitting. That is, they built the foundation of their empire on the OS market (Windows), and the Software development market (BASIC). They should focus on their windows platform, because they have really let it go down the crapper lately and although I don't think anyone is quite capable of challenging Microsoft's monopoly on the OS market yet. You can only skate on market share for so long before you wear a hole in the ice.

Examples of this include, WEBtv, Virtual PC, Microsoft Surface (http://en.wikipedia.org/wiki/Microsoft_Surface) (table top PC that cost $12,000), Silverlight (http://en.wikipedia.org/wiki/Silverlight) (trying to compete with flash).

Sure there are the few exceptions to this such as the xbox, and the xbox 360 that actually do quite well. But that doesn't change the fact that Microsoft really needs to cut the fat and focus more attention to it's core products that actually generate revenue, such as the xbox and windows franchise.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: David on July 05, 2010, 02:21:58 pm
To me this seems like another product trying to solve a problem that doesn't really exist in the first place! As Dave mentioned, I believe it will probably cause more confusion than anything else!
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 05, 2010, 03:16:13 pm
Especially if devices using this no longer put a battery orientation icon in the battery compartment.  If it succeeds even marginally, not all devices will use it, so if one is mindless enough to insert batteries pellmell into Instaload, would they do the same to the majority of devices that aren't Instaload?  

But, most designs use polarity protection on battery compartments.  OTAH, the future is low power devices.  The typical circuit protection is a diode or similar p-n junction device, and this becomes quite a large V drop as devices start leaning towards single battery supplies.  If you remove this protection, then an idiot proof battery orientation system becomes more crucial.

To me this seems like another product trying to solve a problem that doesn't really exist in the first place! As Dave mentioned, I believe it will probably cause more confusion than anything else!
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: charliex on July 05, 2010, 07:17:29 pm
I'm amazed people these days still think Microsoft has some sort of business model problem.  Yes they've had a lot of failures, but even with those they've still got plenty of money and a huge market share, and they're willing to try different things out.

Developing products that are outside its revenue focus is called research and development, which they're really good at too, they have some super smart people up there. It's easy to pick a handful of things and poke fun at it, carrot top makes an easy living from easy hanging fruit.

Seriously, they're massively successful. I'd be insanely happy with a fraction of one percent of their success.

Though no doubt it'll get a lot of blog traffic, microsoft, apple, etc all are good for traffic spiking. just have to look at places like engadget for that. There are a lot of people that can ride on the back of a beast as big as them.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: mikeselectricstuff on July 05, 2010, 11:55:52 pm
File under "Nothing to see here...!"
Totally agree that this is a potentially flawed solution to a non-problem.
Would having this clip swing anyone's decision to buy a product? No.
Would having the name Microsoft asociated with your product actually deter buyers? Maybe.
Why would you pay M$ a licence fee to use it in your product? er....
Will you see Chinese clones of this very soon? Definitely.
 

 
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: NiHaoMike on July 06, 2010, 12:32:49 am
Things will get interesting when some brand of battery has dimensions such that it would short circuit in that holder, causing Microsoft to recall their "technology"...
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: PetrosA on July 06, 2010, 02:17:11 am
A weakness I see in the design:

- Layout will be limited to side-by-side, one row deep which will force product design around the battery holder. If you go two deep, you're back to having to match polarity, at least on pairs and many products use a two-deep layout.

I'm stumped by one thing, namely how to get a circuit like this to work with more than two batteries in series. I've been sketching different variations for about 20 minutes and I can't see any way to make the loop without shorting it out at some point once you go to three batteries. Anyone else know how it's done?
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: EEVblog on July 06, 2010, 02:49:55 am
I'm stumped by one thing, namely how to get a circuit like this to work with more than two batteries in series. I've been sketching different variations for about 20 minutes and I can't see any way to make the loop without shorting it out at some point once you go to three batteries. Anyone else know how it's done?

Each cell has it's own pair of dual polarity contacts and hence it's own + and - output, so you simply wire them in series just like you would any other single cell battery holder.

As you said, you can't go two cells in series end-on-end as in common is 2+ cell cylindrical torches for example.

Dave.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: avrfreaks on July 06, 2010, 04:38:26 am
I been keeping tabs on Microsoft and actually there first product to use this Insta-Load is going to be there Mice, Wireless Keyboards, IIS 8 Server Loading Control. Actually there will be software written by a few Microsoft people, and battery loading will eventually take the laptop market, assuming that apple keeps off.

~~~~Great Dave~~~~
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 06, 2010, 11:42:32 am

I can see production houses with Microsoft products forced into using these as part of their specification, so at least there will be some demand for these products.

But you suggest laptops will work off AA batteries in the near future?  As is, mice, KB do use AA or AAA so I can see that conversion instantly, but laptops I can't see happen as individual Li cells cost more than the total cells needed in a battery pack, and no strides have been made in power consumption for real laptops in the past 10 years due to the LCD and hard drive needs.  Some netbooks maybe, but they are quite slow to run 10 hours on standard Li packs.

If you have an URL which mentions laptops please post.


I been keeping tabs on Microsoft and actually there first product to use this Insta-Load is going to be there Mice, Wireless Keyboards, IIS 8 Server Loading Control. Actually there will be software written by a few Microsoft people, and battery loading will eventually take the laptop market, assuming that apple keeps off.

~~~~Great Dave~~~~
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: avrfreaks on July 06, 2010, 03:59:24 pm
Here is a few links: There main market is keyboards + mice but using a Solid State drive and more digital; they can work on the netbooks first and work there way up the line. More are more are coming and jumping in like Sony + Dell Laptop Company.

http://www.microsoft.com/presspass/press/2010/jul10/07-01instaloadpr.mspx

http://www.microsoft.com/hardware/mouseandkeyboard/licensing/instaloadoverview.mspx

http://www.pocket-lint.com/news/34072/microsoft-plan-change-battery-insertion
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: Simon on July 06, 2010, 05:16:39 pm
It's a solution to a nonproblem and really if we make the world fool proof all the future generations will be is fools !

As for M$ having been so great and got so far yea: they started on stolen code forced their way to market by making everything incompatible with their own stuff, using crap code and getting developers to use their own crap programming environments so they are tied up to M$ (ever tried running a .Net program..... ? it is so ssslllo0oooooooooooooowww).

now they are getting bright engineering ideas ? gah humbug the only thins M$ knows how to do is dictate, oh and by the way they trust their own crappy OSes so much that they have Linux firewalls at M$ hahahaha I've never known such a joke of a company, yea they are great, so are corrupt politicians !!!
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 06, 2010, 06:46:50 pm
Thanks!  I used an old DOS based 'palmtop' that was powered by AA and it worked very well for early modem-BBS things, I got about 6-8h of battery life.  But haven't seen anything like those since. 


(http://www.thocp.net/hardware/pictures/pda/hp_100_lx.jpg)

Here is a few links: There main market is keyboards + mice but using a Solid State drive and more digital; they can work on the netbooks first and work there way up the line. More are more are coming and jumping in like Sony + Dell Laptop Company.

http://www.microsoft.com/presspass/press/2010/jul10/07-01instaloadpr.mspx

http://www.microsoft.com/hardware/mouseandkeyboard/licensing/instaloadoverview.mspx

http://www.pocket-lint.com/news/34072/microsoft-plan-change-battery-insertion
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: charliex on July 06, 2010, 06:48:29 pm
Thanks!  I used an old DOS based 'palmtop' that was powered by AA and it worked very well for early modem-BBS things, I got about 6-8h of battery life.  But haven't seen anything like those since. 

http://www.open-pandora.org/
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 06, 2010, 07:09:24 pm
Thanks!  Alas, while its likely to be a new palmtop it doesn't use AA batteries.

Details here:

http://en.wikipedia.org/wiki/Pandora_%28console%29



Thanks!  I used an old DOS based 'palmtop' that was powered by AA and it worked very well for early modem-BBS things, I got about 6-8h of battery life.  But haven't seen anything like those since. 

http://www.open-pandora.org/

Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: EEVblog on July 06, 2010, 09:52:04 pm
My Psion 5 takes AA batteries.
As does my old Tandy 100!

Dave.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: PetrosA on July 06, 2010, 10:41:09 pm

Each cell has it's own pair of dual polarity contacts and hence it's own + and - output, so you simply wire them in series just like you would any other single cell battery holder.

As you said, you can't go two cells in series end-on-end as in common is 2+ cell cylindrical torches for example.

Dave.

That's just it... I can see how to do it if the batteries are wired parallel, which maintains the single cell voltage, but if you wanted 4 cells in series for 6V or 6 cells for 9V, will this invention work or will the products be limited to 1.5V at some greater A/hr rating?
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: EEVblog on July 06, 2010, 10:43:47 pm

Each cell has it's own pair of dual polarity contacts and hence it's own + and - output, so you simply wire them in series just like you would any other single cell battery holder.

As you said, you can't go two cells in series end-on-end as in common is 2+ cell cylindrical torches for example.

Dave.

That's just it... I can see how to do it if the batteries are wired parallel, which maintains the single cell voltage, but if you wanted 4 cells in series for 6V or 6 cells for 9V, will this invention work or will the products be limited to 1.5V at some greater A/hr rating?

It works either way, series or parallel, as I said. But it requires a set of these dual polarity contacts at each end.
These contacts do exactly as they say, they give you +/- output terminals whichever way you insert the battery. So you are free to wire them in series or parallel after that.

Dave.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: PetrosA on July 07, 2010, 02:27:17 am

Each cell has it's own pair of dual polarity contacts and hence it's own + and - output, so you simply wire them in series just like you would any other single cell battery holder.

As you said, you can't go two cells in series end-on-end as in common is 2+ cell cylindrical torches for example.

Dave.

That's just it... I can see how to do it if the batteries are wired parallel, which maintains the single cell voltage, but if you wanted 4 cells in series for 6V or 6 cells for 9V, will this invention work or will the products be limited to 1.5V at some greater A/hr rating?

It works either way, series or parallel, as I said. But it requires a set of these dual polarity contacts at each end.
These contacts do exactly as they say, they give you +/- output terminals whichever way you insert the battery. So you are free to wire them in series or parallel after that.

Dave.

Man do I feel stupid. I must have been overthinking the whole thing while I was doing my drawing and I got blocked. I was trying to imagine the whole thing as a series with the final positive and negative leads coming off of the first module instead of one from the first, one from the last. In my defense, I do work mostly with AC ;)
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: imanhp on July 07, 2010, 02:02:23 pm
I would be surprised if they would get the patent approved due to this (5,431,575) older and very similar patent: http://www.google.com/patents/about?id=TGYgAAAAEBAJ&dq=5,431,575
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: TheDirty on July 07, 2010, 02:18:32 pm
I would be surprised if they would get the patent approved due to this (5,431,575) older and very similar patent: http://www.google.com/patents/about?id=TGYgAAAAEBAJ&dq=5,431,575
I thought they already got the patent, but ya, you found it.  That's the exact technology, already patented.  Minor differences that I can see from a quick scan, but really the same thing.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: David on July 07, 2010, 04:30:53 pm
I would be surprised if they would get the patent approved due to this (5,431,575) older and very similar patent: http://www.google.com/patents/about?id=TGYgAAAAEBAJ&dq=5,431,575

It looks as if that patent is almost identical!
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: Simon on July 07, 2010, 04:58:32 pm
did M$ really do anything of their own ???? no not that i can recall, half their OS is subcontracted and then they go messing with electronics......
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: ThunderSqueak on July 07, 2010, 06:18:53 pm
I have 2 computers that take AA batteries...

a Tandy TRS-80 Model 100 (maxed to 32k ram and has an assembler option rom installed) which According to Gates, "part of my nostalgia about this machine is this was the last machine where I wrote a very high percentage of the code in the product".

and an HP 200LX that has PC-GEOS installed on it.  Both still work great :)




Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 07, 2010, 07:27:11 pm
I did know the Model 100 used AA, that's a lot of AA I guess!

(http://oldcomputers.net/pics/trs80-100.jpg)

While I like Li for power density, I'm not a fan of their erratic behavior if left unused or worse if fully discharged and stored, nor that it just ages and dies even if unused or violently explodes if charged improperly.

(http://eetdnews.lbl.gov/nl27/images/eetd-nl27-4a.jpg)

In my personal experience, I've seen some of Chinese no-name Li get unbearably hot and start deforming its casing for no apparent reason, it was fine when it was young.

NiMH can be stored as is and will stay relatively fresh if unused for years,

http://www.mrs.org/s_mrs/sec_subscribe.asp?CID=12302&DID=236622&action=detail

... just cycle them to get them awake, and if improperly overcharged will just bubble out and die a graceful but user safe death.

I've had this happen to me 2x but not as severe, using again, no-name Chinese NiMH cells charged properly in a charger.

(http://tlb.org/nimhboom2.jpg)

Old NiMH past its lifetime get senile in terms of mAh and just sleep permanently neither blowing up, overheating, nor holding a charge.

So, I'm not just a fan of NiMH, AA, and AAA for its ubiquity and ease of working with, but its safety and low cost.  While the form factor leaves problems, an AA powered device from the 1990s likely will work today by just putting fresh cells into them, while a Li powered device will need a new battery or pack that may be difficult to find.


I have 2 computers that take AA batteries...

a Tandy TRS-80 Model 100 (maxed to 32k ram and has an assembler option rom installed) which According to Gates, "part of my nostalgia about this machine is this was the last machine where I wrote a very high percentage of the code in the product".

and an HP 200LX that has PC-GEOS installed on it.  Both still work great :)





Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: charliex on July 07, 2010, 10:28:19 pm
A lot of laptops take A/AA cell batteries (and other sizes) they're just packed into a single unit, my vaio tr2a extended is like 9 of them if i recall.

Even some car batteries are just a whole stack of D cells.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: alm on July 07, 2010, 10:33:33 pm
I think they use 18650 and similar sizes, I don't think there are many Li-Ion batteries in A/AA size, and nickel-based batteries haven't been used in laptops for a long time.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 07, 2010, 11:14:19 pm
To add to Alms comment, Li are not widespread as AA or AAA to avoid accidentally selling them aftermarket or putting them in an AA or AAA required device by mistake.  The base voltage of Li is ~ 3.6V per cell, 3x that of single NiMH, which is the most common form for AA and AAA.

There are various cell types that look similar at face value, until you truly compare them side by side.  14500 is fairly close, but if you do insert it, some can be just a touch short and narrow.

(http://www.dealextreme.com/customerphotos/0975-044a6af7-a22c-4411-a0c9-342df98e8703.jpg)

A lot of laptops take A/AA cell batteries (and other sizes) they're just packed into a single unit, my vaio tr2a extended is like 9 of them if i recall.

Even some car batteries are just a whole stack of D cells.

Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: alm on July 07, 2010, 11:34:30 pm
They are available in 1/2AA sizes (at least the primary lithium cells are), so you could put two of those in series if you're really motivated ;).
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: charliex on July 07, 2010, 11:37:38 pm
yeah 14500s are AA sized 50mm x 14mm
 
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: NiHaoMike on July 07, 2010, 11:39:01 pm
To add to Alms comment, Li are not made AA or AAA to avoid accidentally selling them aftermarket or putting them in an AA or AAA required device by mistake.  The base voltage of Li is ~ 3.6V per cell, 3x that of single NiMH, which is the most common form for AA and AAA.
I have 4 AAs that are LiFePO4. I bought them at Wal-Mart, probably originally intended for toy airplanes or something. (That was when LiFePO4 was just appearing on the market, very surprising to see them in a store that does not specialize in electronics.)
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: DJPhil on July 08, 2010, 12:53:16 am
. . . PC-GEOS . . .

I did a double take on that one!  :o

I had to look it up. It seems the GEOS I remember for the Commodore (http://en.wikipedia.org/wiki/GEOS_%288-bit_operating_system%29) was made by the same folks, and after changing hands a few times it's still going. It's now known as the Breadbox Ensemble (http://en.wikipedia.org/wiki/Breadbox_Ensemble), and the last update was Aug 2009!

Makes me wish I'd have kept up better, I was busy messing with Windows. :(
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: Zero999 on July 08, 2010, 08:12:34 am
It would be cool to have a laptop which takes standard AA batteries but it would need quite a lot of them, say 14V for a nominal voltage of 16.8V, 21V hot off the charger. The trouble is it would need to be quite large to accomodate all those batteries and it would need some protection to prevent the user doing something stupid like using ordinary alkaline cells. Still I like the idea of not having to go to a specialist supplier to replace the batteries.

Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 08, 2010, 10:15:18 am
If mA requirements are reduced, DC-DC conversion is about 90% efficient and can generate 5V easily from 1.2V.  The smaller the difference between required and supplied voltage, the more efficient the conversion is.

The real problem with AA is mostly the form factor than the power density.  The mass market is driven equally but style, rather than economy of use.  To keep the demand for electronics high, longevity isn't tops on manufacturer's list, so if you find an AA powered device, grab it while you can.

For example, in the exploding eReader market, the Ectaco jetbook lite, also known in China as the Dr Yi reader, has an AA powered version, and its sweet, IMHO.  Other versions are Li powered.  There is also another clone the Libre, but all 3 have different firmwares so they are more cousins than identical twins.

Dr Yi, Jetbook and Libre:

(http://4.bp.blogspot.com/_PyWKNgTzEhY/SVl_xfCrW5I/AAAAAAAADu8/aA0XAPZQ4M0/s400/DrYi.jpg)(http://ak.buy.com/PI/0/500/213401968.jpg)
(http://www.best-ereaders.com/wp-content/gallery/aluratek-libre-reader/aluratek-libre-actual-size.jpg)

It would be cool to have a laptop which takes standard AA batteries but it would need quite a lot of them, say 14V for a nominal voltage of 16.8V, 21V hot off the charger. The trouble is it would need to be quite large to accomodate all those batteries and it would need some protection to prevent the user doing something stupid like using ordinary alkaline cells. Still I like the idea of not having to go to a specialist supplier to replace the batteries.


(http://)
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: charliex on July 08, 2010, 04:46:37 pm
I guess i can't see the desire for wanting AA's over 18600 or packs. They're going to be workable for at least 6 months, then its typically just lower capacity. Which AA's aren't a good density anyway.  In most places i've been you can find a store that'll have some of the most common packs if you get stuck.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 09, 2010, 01:28:43 am
Uniformity.  I can use the same cells and a single type of AA/AAA charger to work many devices, AA/AAA is a lot easier to find anywhere in the world, and in a pinch, you can use alkaline disposables too.

Many retail place do carry Li packs but commonly for devices they sell, or for popular devices and all are specifically meant to be user serviceable: e.g. cell phones, PSP, digital cameras.  Finding iPods, iPhone, etc., battery packs won't be as easy and are not user serviceable batteries. 

To charge Li pack requires you bring individual chargers with you, or to buy a specific universal charger with the specific adapter per pack.  For AA/AAA its just one charger.

I guess i can't see the desire for wanting AA's over 18600 or packs. They're going to be workable for at least 6 months, then its typically just lower capacity. Which AA's aren't a good density anyway.  In most places i've been you can find a store that'll have some of the most common packs if you get stuck.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: Zero999 on July 09, 2010, 09:34:27 am
he smaller the difference between required and supplied voltage, the more efficient the conversion is.
Only if it uses a buck or boost topology.

Using a transformer based topology means that the efficiency can be the same regardless of the input-output voltage differential.

Quote
The real problem with AA is mostly the form factor than the power density.
Are you sure?

I thought NiMH has a similar Wh/L as Li-ion.

http://en.wikipedia.org/wiki/Nickel_metal_hydride_battery

"NiMH has a volumetric energy density of about 300 W·h/L (1080 MJ/m³), significantly better than nickel-cadmium at 50–150 Wh/L, and about the same as Li-ion at 250-360 W·h/L."

Quote
  The mass market is driven equally but style, rather than economy of use. 

That's true, people are expected to upgrade fairly often.

I don't know, perhaps Li-ion is cheaper per Wh than NiMH.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: charliex on July 09, 2010, 04:41:29 pm
I don't think i'd want an iPhone that ran off AA's , in a laptop with alkaline AA's i doubt you'd make it to the boot screen. Even my old nikon c900 lasts a very short time on 4 alkaline AA's. You could always just make a battery box with a hydra lead that could take AA's and use that for emergencies, i'm sure such things exist, solar chargers etc.

I think I'D rather AA went away , or at least something else became more common. But it seems that for that convience of uniformity and mass availability you're giving up stuff thats taller.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 09, 2010, 05:17:32 pm
Yes, you are right on efficiency.

My bad, wrong term, not "power density", but specific energy.  Wh/L Li ~ NiMH, but specific energy Wh/kg Li 2-4x > NiMH.  Here is LiPo, but you can check on other Li varieties.

http://en.wikipedia.org/wiki/Lithium-ion_polymer_battery

As for cost per Wh, it depends on the usage and how the design uses the battery.  There are flame wars in digital camera newsgroups about this subject.  Since the 3.7V 1-2AHpack costs about $6-10, aftermarket, which equivalent is 3 NiMH cells 2-2.7AH ist $2-3@ = $6-10, they are about even.

http://batterydata.com/

What is certain between Li and NiMH is there are few Li standard sizes, many custom cell sizes, and Li age faster than NiMH after manufacture, so its use it, or lose it by 3-5 years.  Li cells are mostly specific for an intended device, whereas AA NiMH are generic sizes can be used on multiple devices, if you plan your device purchases to insure it supports AA.  NiMH loses capacity based on charge/discharge cycles, so the more cycles the faster it ages.

If NiMH is just stored at room temperature charged, it will still be usable many years after LiPo no longer works.  This assumes on NiMH you recondition it before use after stored, and you never deep discharge it past 0.5V by leaving it in a device left ON. I have NiMH cells still in service, between 7-10 years old. 




he smaller the difference between required and supplied voltage, the more efficient the conversion is.
Only if it uses a buck or boost topology.

Using a transformer based topology means that the efficiency can be the same regardless of the input-output voltage differential.

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The real problem with AA is mostly the form factor than the power density.
Are you sure?

I thought NiMH has a similar Wh/L as Li-ion.

http://en.wikipedia.org/wiki/Nickel_metal_hydride_battery

"NiMH has a volumetric energy density of about 300 W·h/L (1080 MJ/m³), significantly better than nickel-cadmium at 50–150 Wh/L, and about the same as Li-ion at 250-360 W·h/L."

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  The mass market is driven equally but style, rather than economy of use.

That's true, people are expected to upgrade fairly often.

I don't know, perhaps Li-ion is cheaper per Wh than NiMH.
Title: Re: Blog #98 Micro$oft's Patented "Instaload" battery holders
Post by: saturation on July 09, 2010, 05:53:26 pm
Yes, neither would I, NiMH specific energy isn't practical for cellphone or laptop use.  We aren't even considering alkaline chemistry, because it cannot deliver high current. 

Li still cost more to manufacture versus NiMH in AA form, so for sheer economy of running, NiMH really is just the rechargeable version of were an alkaline battery is applicable.

As for wanting AA to go away, that maybe.  But if you had to choose what your device uses where both Li and NiMH AA are applicable, the bigger question is the importance of size, and weight over economy of operation.



I don't think i'd want an iPhone that ran off AA's , in a laptop with alkaline AA's i doubt you'd make it to the boot screen. Even my old nikon c900 lasts a very short time on 4 alkaline AA's. You could always just make a battery box with a hydra lead that could take AA's and use that for emergencies, i'm sure such things exist, solar chargers etc.

I think I'D rather AA went away , or at least something else became more common. But it seems that for that convience of uniformity and mass availability you're giving up stuff thats taller.