/sci/ - Science & Math

[Anonymous No.5481331]

what's the deal with batteries?
why are they all rated at multiples of .75v

[Solardarity !DNRaYdJbog No.5481340]

>>5481331

I think that's just how they're set out by the manufacturer.

It's entirely possible to vary the electrolytes and electrodes in a battery to vary the voltage over a large range but that's not very smart on the manufacturer's part, as producing 1v, 1.1v, 1.2v etc. batteries as an example just wouldn't sell.

So the manufacturers make them in discrete, pre-determined sizes so that they can both make a profit without wasting money on pointless voltage intervals AND they're uniform sizes/ voltages for use in a wide range of devices.

(We have A, AA, AAA, D etc. batteries which are universal sizes that are accepted by all kinds of devices.. It's a bit more efficient this way as opposed to making all these inbetween sizes that nobody will use)

[Anonymous No.5481359]

>>5481340
nah it's an extra credit question in class
can't for the life of me googlefu the answer

[Anonymous No.5481376]

>>5481331
>why are they all rated at multiples of .75v

They aren't.

SLA is 2.0V, NiZn is 1.6V, LiFeS2 is 1.8V, LiFePo is 3.3V, etc... voltage is determined by chemistry, and nature isn't so accommodating as to break everything down into an arbitrary multiple.

[Anonymous No.5481382]

>>5481376
i noticed that too on the wikipedia page for batteries
i'm guessing he wants some answer relating to the chemistry of alkaline batteries or something

[Anonymous No.5481446]

>>5481331
They aren't multiples of .75V. Alkaline batteries are in multiples of 1.5V, because single alkaline cell provides 1.5V. Ie 9V battery has 6 tiny cells in series (in some cases you can dismantle and get some AAAA batteries out of it).

The wikipedia page shows quite clearly how the voltage is determined, it's all chemistry.

http://en.wikipedia.org/wiki/Alkaline_batteries#Chemistry

[Anonymous No.5481473]

>>5481446
>>5481446
thanks