Looking at replacing the AAA NiAh rechargable batteries in a Binatone
phone. They seem to have lost some of the original capacity when used
during calls.

Originally supplied with 2 off 1.2v 650 mAh.

What is the significance of the last value? Could a 1000mAh be used
instead. Would that increase the 'storage' period?

David J

On Mon, 28 Sep 2009 14:01:12 +0100, David J
wrote:


What is the significance of the last value?

It relates to the amount of energy stored in the battery expressed as
the number of mA it can supply for one hour (although it is actually
measured at a 5 or 10 hour discharge rate as using a one hour rate
would be misleading).

Rather simplistically 650mA battery can supply 65mA for 10 hours or
130mA for 5 hours.

Could a 1000mAh be used instead.

Yes

Would that increase the 'storage' period?

If by that you mean would it increase the use you got out of the
phone between charges then yes it would.

On Mon, 28 Sep 2009 14:13:01 +0100, Peter Parry
wrote:

On Mon, 28 Sep 2009 14:01:12 +0100, David J
wrote:


What is the significance of the last value?

It relates to the amount of energy stored in the battery expressed as
the number of mA it can supply for one hour (although it is actually
measured at a 5 or 10 hour discharge rate as using a one hour rate
would be misleading).

Rather simplistically 650mA battery can supply 65mA for 10 hours or
130mA for 5 hours.

Could a 1000mAh be used instead.

Yes

Would that increase the 'storage' period?

If by that you mean would it increase the use you got out of the
phone between charges then yes it would.


Thanks for all the replies.

My slight confusion is from trying to get an explanation on Wiki he
http://en.wikipedia.org/wiki/Rechargeable_batteries

where there is a comparison table for different types of rechargeable
cells. The parameter that looks closest to the value in mAh we have
discussed above is described as Specific Power, and is measured in
W/kg. The 'capacity' is not listed.

For the NiMh type they list a Power range of 250 - 1000. But that
unit is more to do with 'efficiency' (as a power-to weight ratio)
rather than 'capacity' surely?

David J

In message , David J
writes


Thanks for all the replies.

My slight confusion is from trying to get an explanation on Wiki he
http://en.wikipedia.org/wiki/Rechargeable_batteries

where there is a comparison table for different types of rechargeable
cells. The parameter that looks closest to the value in mAh we have
discussed above is described as Specific Power, and is measured in
W/kg. The 'capacity' is not listed.

For the NiMh type they list a Power range of 250 - 1000. But that
unit is more to do with 'efficiency' (as a power-to weight ratio)
rather than 'capacity' surely?

That page shows mass-efficiency and volumetric efficiency, watt-hours
per litre. But that particular article is written from an academic
viewpoint comparing different battery technologies, rather than being
written for someone who wants to know which pack to choose at the
supermarket.

It doesn't mention the new low discharge rate "hybrid" NiMH batteries.
These might be a better choice for your phone because their
self-discharge rate is lower. If you find that your batteries have gone
flat even though you haven't used the phone then these new batteries
might be a good choice for you. You can recognise them because they are
usually sold fully charged.


--
Bernard Peek

Bernard Peek wrote:
It doesn't mention the new low discharge rate "hybrid" NiMH batteries.
These might be a better choice for your phone because their
self-discharge rate is lower. If you find that your batteries have gone
flat even though you haven't used the phone then these new batteries
might be a good choice for you. You can recognise them because they are
usually sold fully charged.

It depends if the phone is kept on the cradle most of the time. If it is,
the batteries will be on trickle charge so the self-discharge won't matter.
If you keep the phone switched on but off the cradle, the batteries will
probably go flat in a week or two anyway. It's only if you turn the phone
off for months that the self-discharge becomes an issue.

Personally I'd buy a cheap'n'nasty pair of batteries for a phone, as you
can't be sure the charger is any good. Unless you talk for hours and hours
on end without putting the phone back on the cradle, the batteries are
probably going to be sufficient - higher capacity is better. Until the
charger kills them, at which point you just have to buy some new ones.

Theo

On Sep 28, 6:07*pm, Theo Markettos
wrote:
Bernard Peek wrote:
It doesn't mention the new low discharge rate "hybrid" NiMH batteries.
These might be a better choice for your phone because their
self-discharge rate is lower. If you find that your batteries have gone
flat even though you haven't used the phone then these new batteries
might be a good choice for you. You can recognise them because they are
usually sold fully charged.

It depends if the phone is kept on the cradle most of the time. *If it is,
the batteries will be on trickle charge so the self-discharge won't matter.

In message , David J
writes
Looking at replacing the AAA NiAh rechargable batteries in a Binatone
phone. They seem to have lost some of the original capacity when used
during calls.

Originally supplied with 2 off 1.2v 650 mAh.

What is the significance of the last value? Could a 1000mAh be used
instead. Would that increase the 'storage' period?

Current is measured in Amps and milliamps. A cell with a capacity of 650
mAH would in theory deliver 650mA for one hour then go flat, or perhaps
325mA for two hours. Your 1000mA cell has about a third more storage
capacity than the old ones and so should in theory last a third longer.

In practise the time between charges is also dependent on the cells'
self-discharge rate. But you can safely use 1000mA cells and should
expect to be able to use the phone for longer between charges.



--
Bernard Peek

In uk.d-i-y, David J wrote:
Looking at replacing the AAA NiAh rechargable batteries in a Binatone
phone. They seem to have lost some of the original capacity when used
during calls.

Originally supplied with 2 off 1.2v 650 mAh.

What is the significance of the last value? Could a 1000mAh be used
instead. Would that increase the 'storage' period?

Yes and yes, as long as you can make them fit physically.

--
Mike Barnes

On Mon, 28 Sep 2009 14:01:12 +0100, David J wrote:
Looking at replacing the AAA NiAh rechargable batteries in a Binatone
phone. They seem to have lost some of the original capacity when used
during calls.

Originally supplied with 2 off 1.2v 650 mAh.

What is the significance of the last value? Could a 1000mAh be used
instead. Would that increase the 'storage' period?

It's a very coarse indication of how long they will work, under load.
However a lot of battery makers consider this figure more of a marketing
tool - which allows them to charge more, simply by writing a bigger
number of their products. It's almost impossible to verify the mAh rating
of a battery as there are too many variables and dependencies on how it
is used. A higher value may mean the batteries will supply more juice,
ot it may just mean the manufacturer is less troubled my a conscience
than others.
However, the capacity of even good brands can be killed by having a poor
charger in the phone's base - in which case no amount of mAh will help,
if the phone overcharges and thereby destroys the batteries.

David J wrote:
Looking at replacing the AAA NiAh rechargable batteries in a Binatone
phone. They seem to have lost some of the original capacity when used
during calls.

Originally supplied with 2 off 1.2v 650 mAh.

What is the significance of the last value?

not a lot

Could a 1000mAh be used
instead.

yes.

Would that increase the 'storage' period?

No.

David J

On Mon, 28 Sep 2009 14:01:12 +0100, David J wrote:

What is the significance of the last value? Could a 1000mAh be used
instead. Would that increase the 'storage' period?

And be aware that Lidl have 4 x AAA, 4 x AA, 2 x C, 2 x D, or 9v NiMH
batteries on offer from the 1st Oct for £2.49/pack. The AA size are
2500mAHr. These may well be fast to disappear items...

--
Cheers
Dave.

On Mon, 28 Sep 2009 16:13:52 +0100, Dave Liquorice wrote:

On Mon, 28 Sep 2009 14:01:12 +0100, David J wrote:

And be aware that Lidl have 4 x AAA, 4 x AA, 2 x C, 2 x D, or 9v NiMH
batteries on offer from the 1st Oct for £2.49/pack. The AA size are
2500mAHr. These may well be fast to disappear items...

Last time they had these on offer I bought a load of the AAAs. I generally
use them in LED torches and they get quite a bit of use, and have held up
well.

--
John Stumbles

Little Johnny's gone away, his like we'll see no more
For what he thought was H20 was H2SO4

On Sep 28, 2:01*pm, David J wrote:

Looking at replacing the AAA NiAh rechargable batteries in a Binatone
phone. *They seem to have lost some of the original capacity when used
during calls.

Originally supplied with 2 off 1.2v 650 mAh.

What is the significance of the last value? *Could a 1000mAh be used
instead. *Would that increase the 'storage' period?

yes and yes. IIRC Poundland have 2 AAA rechargeables for £1. Either
650 or 350mAh, I forget.


NT

NT wrote:
yes and yes. IIRC Poundland have 2 AAA rechargeables for ?1. Either
650 or 350mAh, I forget.

350mAh. And their 2xAAs for a pound are 850mAh. I thought of this thread
while I was passing them today :-)

Theo

On 30 Sep 2009 01:07:40 +0100 (BST), Theo Markettos wrote:

And their 2xAAs for a pound are 850mAh. I thought of this thread while
I was passing them today :-)

0.0588/mAHr

Where as Lidl (on offer from tommorow) 4 x AA are 2500mAHr and £2.49
(0.0249/mAHr).

IIRC the Lidl 4 x AAA are 850mAHr again for £2.49 (0.0732p/mAHr) half
the price per mAHr of poundland.

--
Cheers
Dave.

On Sep 30, 7:56*am, "Dave Liquorice"
wrote:
On 30 Sep 2009 01:07:40 +0100 (BST), Theo Markettos wrote:

And their 2xAAs for a pound are 850mAh. *I thought of this thread while
I was passing them today :-)

0.0588/mAHr

Where as Lidl (on offer from tommorow) 4 x AA are 2500mAHr and £2.49
(0.0249/mAHr).

IIRC the Lidl 4 x AAA are 850mAHr again for £2.49 (0.0732p/mAHr) half
the price per mAHr of poundland.

it really comes down to whats near the purchaser, getting there will
cost far more than the cells themselves.


NT

On Wed, 30 Sep 2009 01:59:49 -0700 (PDT), NT wrote:

it really comes down to whats near the purchaser, getting there will
cost far more than the cells themselves.

This is true. The nearest Lidl is 30 miles away so to drive there (60
mile round trip) costs about £20. Don't know where the nearest
Poundland is, but it'll be of the same order whether it's in Penrith,
Carlisle or Hexham.

Of course I wouldn't do a single trip but make it part of a larger
one visiting other places. There would be extra mileage but only 5
miles (about £1.50).

--
Cheers
Dave.

On Wed, 30 Sep 2009 07:56:44 +0100, Dave Liquorice wrote:

IIRC the Lidl 4 x AAA are 850mAHr again for £2.49 (0.0732p/mAHr) half
the price per mAHr of poundland.

IIRC last year's lot were 1000mAh

--
John Stumbles

This sig intentionally left blank

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember John Stumbles
saying something like:

On Wed, 30 Sep 2009 07:56:44 +0100, Dave Liquorice wrote:

IIRC the Lidl 4 x AAA are 850mAHr again for £2.49 (0.0732p/mAHr) half
the price per mAHr of poundland.

IIRC last year's lot were 1000mAh

6 months ago, the ones I got from Lidl's were 900mAHr. Depends on what
supplier deals they've reached I suppose.