Cheap rechargable batteries

Those of us that can't afford the luxury of hub dynamos may be interested
in fairly decent rechargeable batteries at Lidl for the bargain price of
£1.99 (that's less than normal batteries!):

<http://www.lidl.co.uk/gb/home.nsf/pages/c.o.20060126.p.Assorted_Rechargeab
le_Batteries>

Ni-MH batteries (£1.99 a pack):
- 9V battery, 200mAh
- 4 x AAA, 800mAh
- 4 x AA, 2,100mAh
- 2 x C, 3,500mAh
- 2 x D, 4,000mAh

Mark Thompson said:

Those of us that can't afford the luxury of hub dynamos may be interested
in fairly decent rechargeable batteries at Lidl for the bargain price of
£1.99 (that's less than normal batteries!):

<http://www.lidl.co.uk/gb/home.nsf/pages/c.o.20060126.p.Assorted_Rechargeab
le_Batteries>

Ni-MH batteries (£1.99 a pack):
- 9V battery, 200mAh
- 4 x AAA, 800mAh
- 4 x AA, 2,100mAh
- 2 x C, 3,500mAh
- 2 x D, 4,000mAh

That's not a bad capacity for AA and it's an amazing capacity for D (if
it's true). With 4 "D" cells you could run a 2.4W front lamp for a
whole Dunwich Dynamo.

Mark Thompson said:

Those of us that can't afford the luxury of hub dynamos may be interested
in fairly decent rechargeable batteries at Lidl for the bargain price of
£1.99 (that's less than normal batteries!):

<http://www.lidl.co.uk/gb/home.nsf/pages/c.o.20060126.p.Assorted_Rechargeab
le_Batteries>

Ni-MH batteries (£1.99 a pack):
- 9V battery, 200mAh
- 4 x AAA, 800mAh
- 4 x AA, 2,100mAh
- 2 x C, 3,500mAh
- 2 x D, 4,000mAh

That's not a bad capacity for AA and it's an amazing capacity for D (if
it's true). With 4 "D" cells you could run a 2.4W front lamp for a
whole Dunwich Dynamo.

Zog The Undeniable said:

That's not a bad capacity for AA and it's an amazing capacity for D (if
it's true). With 4 "D" cells you could run a 2.4W front lamp for a
whole Dunwich Dynamo.

4Ah is what you get from one of those moped batteries they supply with
the Smart sets; (which should do 10h on 2.4W) have been looking to
convert one lamp to 2.4v 2xD operation for night rides, will have to do
a bench test with some alkalines first.

Zog The Undeniable said:

That's not a bad capacity for AA and it's an amazing capacity for D (if
it's true). With 4 "D" cells you could run a 2.4W front lamp for a
whole Dunwich Dynamo.

4Ah is what you get from one of those moped batteries they supply with
the Smart sets; (which should do 10h on 2.4W) have been looking to
convert one lamp to 2.4v 2xD operation for night rides, will have to do
a bench test with some alkalines first.

"Zog The Undeniable" <[email hidden]> wrote in message
news:43da914b.0@entanet

Quoted message said:

That's not a bad capacity for AA and it's an amazing capacity for D
(if it's true). With 4 "D" cells you could run a 2.4W front lamp for
a whole Dunwich Dynamo.

Pfffft, that's pants. Check out

http://www.strikalite.co.uk/prodcat_type/18/D/0/NiMh%5FBatteries.html

Good ol' Rog at Strikalite assembled me a pack of 5 of these 9Ah beauties
into a 3x2 'pyramid' which I added an automotive 5A fuse to, and enclosed in
a small aluminium enclosure. The whole caboodle sits of the carrier stays on
my Ultra Galaxy, and when charged using a Jamara charger (also at Stikalite,
but pricy) the capacity is calculated at 10.5 Ah. It powers a pair of Cateye
10w fronts admirably, far better than the silly 2.2Ah sticks they came with,
and about the same weight. I'll take a pic and upload it tomorrow.

I have no connection to Strikalite, other than being a satisfied customer
for the last 10 years or so... they fulfill all my battery requirements.

Tim

--
Sent from Birmingham, UK timdunne at blueyonder.co.uk
'God's electrician sparked up the heavens once again, heading northbound
on the 7:10. And the lord said let there be commuters...' - Thea Gilmore
Look, mum, an anorak on a bike! Check out www.nervouscyclist.org

"Zog The Undeniable" <[email hidden]> wrote in message
news:43da914b.0@entanet

Quoted message said:

That's not a bad capacity for AA and it's an amazing capacity for D
(if it's true). With 4 "D" cells you could run a 2.4W front lamp for
a whole Dunwich Dynamo.

Pfffft, that's pants. Check out

http://www.strikalite.co.uk/prodcat_type/18/D/0/NiMh%5FBatteries.html

Good ol' Rog at Strikalite assembled me a pack of 5 of these 9Ah beauties
into a 3x2 'pyramid' which I added an automotive 5A fuse to, and enclosed in
a small aluminium enclosure. The whole caboodle sits of the carrier stays on
my Ultra Galaxy, and when charged using a Jamara charger (also at Stikalite,
but pricy) the capacity is calculated at 10.5 Ah. It powers a pair of Cateye
10w fronts admirably, far better than the silly 2.2Ah sticks they came with,
and about the same weight. I'll take a pic and upload it tomorrow.

I have no connection to Strikalite, other than being a satisfied customer
for the last 10 years or so... they fulfill all my battery requirements.

Tim

--
Sent from Birmingham, UK timdunne at blueyonder.co.uk
'God's electrician sparked up the heavens once again, heading northbound
on the 7:10. And the lord said let there be commuters...' - Thea Gilmore
Look, mum, an anorak on a bike! Check out www.nervouscyclist.org

Tim Dunne said:

"Zog The Undeniable" <[email hidden]> wrote in message
news:43da914b.0@entanet

Quoted message said:

That's not a bad capacity for AA and it's an amazing capacity for D
(if it's true). With 4 "D" cells you could run a 2.4W front lamp for
a whole Dunwich Dynamo.

Pfffft, that's pants. Check out

http://www.strikalite.co.uk/prodcat_type/18/D/0/NiMh%5FBatteries.html

Good ol' Rog at Strikalite assembled me a pack of 5 of these 9Ah beauties
into a 3x2 'pyramid' which I added an automotive 5A fuse to, and enclosed in
a small aluminium enclosure. The whole caboodle sits of the carrier stays on
my Ultra Galaxy, and when charged using a Jamara charger (also at Stikalite,
but pricy) the capacity is calculated at 10.5 Ah. It powers a pair of Cateye
10w fronts admirably, far better than the silly 2.2Ah sticks they came with,
and about the same weight. I'll take a pic and upload it tomorrow.

I have no connection to Strikalite, other than being a satisfied customer
for the last 10 years or so... they fulfill all my battery requirements.

What do they weigh? With six of them (7.2V) you could run a dynamo
headlamp [1] all day and all night...depends on the trade-off between
the lack of dynamo drag (say 5W for a Schmidt) and the extra weight you
have to lug uphill, which could partially be offset by a lighter front
hub than the Schmidt.

[1] inevitably overvolted by a dynamo, so 5 batteries (6V) on a 3W 0.5A
bulb doesn't give the brightness you'd expect.

Zog The Undeniable said:

Tim Dunne said:

"Zog The Undeniable" <[email hidden]> wrote in message
news:43da914b.0@entanet

Quoted message said:

That's not a bad capacity for AA and it's an amazing capacity for D
(if it's true). With 4 "D" cells you could run a 2.4W front lamp for
a whole Dunwich Dynamo.

Pfffft, that's pants. Check out

http://www.strikalite.co.uk/prodcat_type/18/D/0/NiMh%5FBatteries.html

Good ol' Rog at Strikalite assembled me a pack of 5 of these 9Ah beauties
into a 3x2 'pyramid' which I added an automotive 5A fuse to, and enclosed in
a small aluminium enclosure. The whole caboodle sits of the carrier stays on
my Ultra Galaxy, and when charged using a Jamara charger (also at Stikalite,
but pricy) the capacity is calculated at 10.5 Ah. It powers a pair of Cateye
10w fronts admirably, far better than the silly 2.2Ah sticks they came with,
and about the same weight. I'll take a pic and upload it tomorrow.

I have no connection to Strikalite, other than being a satisfied customer
for the last 10 years or so... they fulfill all my battery requirements.

What do they weigh? With six of them (7.2V) you could run a dynamo
headlamp [1] all day and all night...depends on the trade-off between
the lack of dynamo drag (say 5W for a Schmidt) and the extra weight you
have to lug uphill, which could partially be offset by a lighter front
hub than the Schmidt.

[1] inevitably overvolted by a dynamo, so 5 batteries (6V) on a 3W 0.5A
bulb doesn't give the brightness you'd expect.

What type of batteries? ISTR that my nimh batteries I use for my LED
lamps though rated at 1.2V seem to read more like 1.3V when fully
charged. Maybe it's my meter. The brightness of the lamp will of of
course drop over time, but I think 1.3x6 = 7.8V might well be
stretching it a bit (I could be wrong of course). You'd probably want
regulation to deal with this, but that might well reduce the
effiiciency.

AA nimh batteries I use are 2300mAh. At 500mA (3W bulb or 2.4+0.6 for
front+rear) you're going to get a run time of 4.6 hours at nominal
capacity, if I've done my sums right. At 1A (giving the dual lamp
functionality of a SON) then you're 2.3 hours. Sufficient for
commuting, I'd think. Not going to run all night though!

Simon

I see Maplin do a Li-Ion rechargable pack (meant for camcorders but
prolly adaptable) which is 2Ah, seems a good trade off between weight
and capacity.

"MartinM" <[email hidden]> wrote in message
news:[email hidden]

Quoted message said:

I see Maplin do a Li-Ion rechargable pack (meant for camcorders but
prolly adaptable) which is 2Ah, seems a good trade off between weight
and capacity.

Not a good idea - LiIon batteries have a tendency to explode if not handled
and treated in accordance with guidelines - one thing they don't like is
deep current draw and vibration.

Tim

--
Sent from Birmingham, UK timdunne at blueyonder.co.uk
'God's electrician sparked up the heavens once again, heading northbound
on the 7:10. And the lord said let there be commuters...' - Thea Gilmore
Look, mum, an anorak on a bike! Check out www.nervouscyclist.org

Tim Dunne said:

"MartinM" <[email hidden]> wrote in message
news:[email hidden]

Quoted message said:

I see Maplin do a Li-Ion rechargable pack (meant for camcorders but
prolly adaptable) which is 2Ah, seems a good trade off between weight
and capacity.

Not a good idea - LiIon batteries have a tendency to explode if not handled
and treated in accordance with guidelines - one thing they don't like is
deep current draw and vibration.

So the cycle mounts for mobile phones have something to deal with
this, or do they all come with, your phone may explode warnings?

Jim.

Tim Dunne said:

"MartinM" <[email hidden]> wrote in message
news:[email hidden]

Quoted message said:

I see Maplin do a Li-Ion rechargable pack (meant for camcorders but
prolly adaptable) which is 2Ah, seems a good trade off between weight
and capacity.

Not a good idea - LiIon batteries have a tendency to explode if not handled
and treated in accordance with guidelines - one thing they don't like is
deep current draw and vibration.

OK thanks. Out of interest does anyone know what the actaul capacity of
the various alkaline D cells on the market is? (the are very secretive
on their packaging).

Tim Dunne said:

"MartinM" <[email hidden]> wrote in message
news:[email hidden]

Quoted message said:

I see Maplin do a Li-Ion rechargable pack (meant for camcorders but
prolly adaptable) which is 2Ah, seems a good trade off between weight
and capacity.

Not a good idea - LiIon batteries have a tendency to explode if not
handled and treated in accordance with guidelines - one thing they
don't like is deep current draw and vibration.

The capacity to weight ratio makes Li-Ion batteries good indeed for
high-power cycle lights as long as some protection is built in or added
for over-charge and over-discharge. See www.lumicycle.co.uk for example.

~PB

Tim Dunne said:

"MartinM" <[email hidden]> wrote in message
news:[email hidden]

Quoted message said:

I see Maplin do a Li-Ion rechargable pack (meant for camcorders but
prolly adaptable) which is 2Ah, seems a good trade off between weight
and capacity.

Not a good idea - LiIon batteries have a tendency to explode if not
handled and treated in accordance with guidelines - one thing they
don't like is deep current draw and vibration.

Lithium polymer are fine under those circumstances though.

Chris
--
Chris Eilbeck
MARS Flight Crew http://www.mars.org.uk/
UKRA #1108 Level 2 UYB
Tripoli UK Member #9527 LSMR

"Chris Eilbeck" <[email hidden]> wrote in message
news:[email hidden]

Quoted message said:

Lithium polymer are fine under those circumstances though.

Highly debatable. I was looking into the technologies and did a little
research, the horror stories are remarkable.

Tim

--
Sent from Birmingham, UK timdunne at blueyonder.co.uk
'God's electrician sparked up the heavens once again, heading northbound
on the 7:10. And the lord said let there be commuters...' - Thea Gilmore
Look, mum, an anorak on a bike! Check out www.nervouscyclist.org

"Jim Ley" <[email hidden]> wrote in message
news:[email hidden]

Quoted message said:

So the cycle mounts for mobile phones have something to deal with
this, or do they all come with, your phone may explode warnings?

Why should they? The people who make cycle mounts wouldn't care - do you
think it's a good idea to subject a mobile to that kind of vibration anyway?
I've dropped a medical Li-ion pack at work and very nearly been badly burned
in the resultant flare-up.

Do a google, this isn't trivial.

Tim

--
Sent from Birmingham, UK timdunne at blueyonder.co.uk
'God's electrician sparked up the heavens once again, heading northbound
on the 7:10. And the lord said let there be commuters...' - Thea Gilmore
Look, mum, an anorak on a bike! Check out www.nervouscyclist.org

Zog The Undeniable said:

Mark Thompson said:

- 2 x D, 4,000mAh

That's not a bad capacity for AA and it's an amazing capacity for D (if
it's true).

Not really - Ansmann do a 8Ah D cell (but I don't know how reliable
the capacity is, though I've seen good reviews of their AA cells).
I've seen D cells with slightly higher than that claimed.

GP do a 7Ah D cell (7Ah min, and I trust GPs figures) -
http://www.farnell.com/datasheets/21819.pdf (recommended discharge
currents to 35A, so that'd be a nice bright light).

Admittedly, farnell want 12.42 quid plus VAT for a single GP cell

regards, Ian SMith
--
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MartinM said:

OK thanks. Out of interest does anyone know what the actaul capacity of
the various alkaline D cells on the market is? (the are very secretive
on their packaging).

Not so much secretive, as the answer can't be usefully quantified in
most cases. The useful (or apparent) capacity is strongly dependant
on the drain current, and somewhat dependant on service conditions and
duty cycle. They could quote a value, but it may or may not actually
resemble what you actually get.

Your best bet is to peruse information intended for commercial users.
I find Farnell to be a good source for data sheets. For example, at
http://www.farnell.com/datasheets/31104.pdf you can find families of
curves for Duracell Ultra M3 D cells.

Typically, upper-end alkaline D cells are in teh 15-18 Ah range.

regards, Ian SMith
--
|\ /| no .sig
|o o|
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