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MS Design Lets You Put Batteries In Any Way You Want
jangel writes "While its strategy for mobile devices might be a mess, Microsoft has announced something we'll all benefit from. The company's patented design for battery contacts will allow users of portable devices — digital cameras, flashlights, remote controls, toys, you name it — to insert their batteries in any direction. Compatible with AA and AAA cells, among others, the 'InstaLoad' technology does not require special electronics or circuitry, the company claims."
I suggest you learn a bit more about electronics. Diodes have a voltage drop, 0.7V for normal diodes, schottky diodes go as low as 0.2V, but that's still a lot if you get only 1.2V to 1.5V from your battery.
And the summery clearly states that it is without circuitry. Which is not that hard to imagine if you LATFPITFA.
This is specifically for battery compartments with a physical parallel configuration, rather than a series configuration.
( 'physical configuration' as in the batteries laying side-by-side, rather than end-to-end, so the batteries' poles never directly touch eachother; unrelated to the electrical circuitry's configuration )
I'm trying to recall the last time I've seen a physical series configuration; but I just realized my old-ass flashlight counts as one.
( it's been replaced years ago by a proper wind-up for emergency cases and a decent Maglite-like one with a rechargable set for more frequent/high intensity beam use )
Do not do it serially. Keep in mind that you can design with batteries in parallel fashion, and then connect the batteries serially logically. The funny thing is, that I DID think about this 3 years ago. For the last 3 years, I have been putting loads of batteries in kids toys and some of them just plained sux to put batteries in.
I prefer the "u" in honour as it seems to be missing these days.
It's probably as cheap to make as regular battery contacts.
It won't be, it requires more peices of material in the contacts themselves (twice as many contacts plus an extra insulating peice) and more wiring (since you have to take both the positive and negative leads to both ends of each battery slot).
BTW you can make contacts that protect against damge from backwards insertion far simpler (and i've seen them in equipment) just by shaping the plastic right at the positive end (basically you put the positive contact inside a slot so the flat negative end can't touch it). The only advantage of these new contacts over that style is that they allow things to work both ways round.
Just hope it is as reliable as normal contacts.
Indeed I have two main concerns with this
1: reliability, how long will these fancy contacts last.
2: failure modes, when normal battery contacts fail they tend to fail by just not making good contact, they can then be cleaned, bent back into shape etc. This thing looks like it could easilly fail in a way that shorts out the battery and looks like it would be difficult to fix poor contacts without ruining the mechanism.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
Except diodes have a foward voltage drop almost as high as a 1.1V battery, so now it would take an extra 2 batteries for a 4 cell device using your "trivial" design.
Besides, no one uses diodes anymore for rectification - that's what fets are for!
You actually CAN recharge ordinary alkalines, but you need a trickle charger like the "battery xtender" and they don't charge to the same level or last nearly as many cycles as proper MiMH ones.
http://en.wikipedia.org/wiki/Schottky_diode
There's also Germanium diodes with a forward voltage drop of about 0.2V. That might still be too much as a typical bridge has to pass current through 2 of them though. I suppose you could then use a boost converter, but that all seems quite wasteful.
Someone invented it before: http://www.freepatentsonline.com/5431575.html (1995)