Hi What are the pros and cons of using recharable AA batteries or a 6V 4Ah
lead acid battery charged by solar power to power a security light?

Janice

Hi What are the pros and cons of using recharable AA batteries or a 6V
4Ah
lead acid battery charged by solar power to power a security light?

Janice

For starters AA rechargeable are less than 0.3Ah
but I suspect I am missing something here...

--
Graham.

%Profound_observation%

"Graham." wrote in message
...

Hi What are the pros and cons of using recharable AA batteries or a 6V
4Ah
lead acid battery charged by solar power to power a security light?

Janice

For starters AA rechargeable are less than 0.3Ah
but I suspect I am missing something here...

--
Graham.

Hi it is just that I saw a security light for sale that uses 3 x AA Ni-Mh
rechargeable batteries and leds and has a solar cell to recharge it and
another one that uses a 6V 4Ah lead acid battery charged by solar power and
a 10 watt halogen bulb so was wondering what would be the best in
replacement of batteries and battery life?
Janice

Janice wrote:
"Graham." wrote in message
...

Hi What are the pros and cons of using recharable AA batteries or a 6V
4Ah
lead acid battery charged by solar power to power a security light?

Janice

For starters AA rechargeable are less than 0.3Ah
but I suspect I am missing something here...

--
Graham.

Hi it is just that I saw a security light for sale that uses 3 x AA Ni-Mh
rechargeable batteries and leds and has a solar cell to recharge it and
another one that uses a 6V 4Ah lead acid battery charged by solar power and
a 10 watt halogen bulb so was wondering what would be the best in
replacement of batteries and battery life?
Janice

I dont know what your question means. here's the battery info though:
http://www.wiki.diyfaq.org.uk/index....d_acid_battery
http://www.wiki.diyfaq.org.uk/index....e=NiMH_battery


NT

In article ,
Janice wrote:
Hi it is just that I saw a security light for sale that uses 3 x AA
Ni-Mh rechargeable batteries and leds and has a solar cell to recharge
it and another one that uses a 6V 4Ah lead acid battery charged by
solar power and a 10 watt halogen bulb so was wondering what would be
the best in replacement of batteries and battery life?

I'd say this is one use where a lead acid isn't a good idea - they don't
like being run flat, unlike Ni-Cads. Unless it's a switched security light
and you won't actually run the batteries low.

--
*Great groups from little icons grow *

Dave Plowman London SW
To e-mail, change noise into sound.

Graham. wrote:

Hi What are the pros and cons of using recharable AA batteries or a 6V
4Ah
lead acid battery charged by solar power to power a security light?

Janice

For starters AA rechargeable are less than 0.3Ah
but I suspect I am missing something here...

All the rechargeable AA batteries I have are way more than 0.3Ah, even
my oldish ones are 1800mAh which is 1.8Ah. I have lots of new ones
which are 2700mAH, that's 2.7Ah. OK, it's less than 4Ah but I bet
that 4 (or possibly 5) AA cells are smaller than the Lead Acid battery.

--
Chris Green

In message ,
wrote
Graham. wrote:

Hi What are the pros and cons of using recharable AA batteries or a 6V
4Ah
lead acid battery charged by solar power to power a security light?

Janice

For starters AA rechargeable are less than 0.3Ah
but I suspect I am missing something here...

All the rechargeable AA batteries I have are way more than 0.3Ah, even
my oldish ones are 1800mAh which is 1.8Ah. I have lots of new ones
which are 2700mAH, that's 2.7Ah. OK, it's less than 4Ah but I bet
that 4 (or possibly 5) AA cells are smaller than the Lead Acid battery.


Surely it depends more on the light output from the LEDs vs the 10W
halogen bulb for the application rather than the battery technology?

An expensive 3 or 5W LED is hardly bright enough for a security light.
It may give enough light to illuminate something the size of a small
patio just to the extent that you will be able to see what is there and
not fall over it.

The OP suggested solar charging. I doubt that at this time of year the
batteries would fully charge during the day and therefore you would be
lucky to get more than an hour of light during the time when you wanted
them most. Just consider those rechargeable garden lights that glow
brightly during the summer nights but never get beyond a hardly visible
glow this time of year.


--
Alan
news2006 {at} amac {dot} f2s {dot} com

Dave Plowman (News) wrote:

In article ,
Janice wrote:
Hi it is just that I saw a security light for sale that uses 3 x AA
Ni-Mh rechargeable batteries and leds and has a solar cell to recharge
it and another one that uses a 6V 4Ah lead acid battery charged by
solar power and a 10 watt halogen bulb so was wondering what would be
the best in replacement of batteries and battery life?

I'd say this is one use where a lead acid isn't a good idea - they don't
like being run flat, unlike Ni-Cads. Unless it's a switched security light
and you won't actually run the batteries low.


I've one of those 500 candlepower spotlights with a gel batterry in it. As
it needs a new battery is there a better repalcement than lead acid?

AJH

On Tue, 30 Dec 2008 21:41:34 +0000, andrew wrote:

I've one of those 500 candlepower spotlights with a gel batterry in it.
As it needs a new battery is there a better repalcement than lead acid?

Depends how long you want the light to run for... I have a similar thing
from memory the bulb is 6v 55W and the battery a 4Ahr SLA. Get about 20
mins run time from it.

The largest AA NiMH are less than 3Ahr so even less run time and I'm not
sure they would take all that kindly to a 10A load either. SLA is robust
and simple, just a bit heavy.

--
Cheers
Dave.

In article ,
andrew wrote:
I'd say this is one use where a lead acid isn't a good idea - they
don't like being run flat, unlike Ni-Cads. Unless it's a switched
security light and you won't actually run the batteries low.


I've one of those 500 candlepower spotlights with a gel batterry in it.
As it needs a new battery is there a better repalcement than lead acid?

Crikey - hope it's a bright night if only 500 candle power. ;-)

With most of these things a complete new one costs less than a replacement
battery.
I'm not sure why there was a fashion for those lead acid handlamps.
Ni-Cads etc are lighter and smaller. Perhaps something to do with
voltage/capacity.

--
*Red meat is not bad for you. Fuzzy green meat is bad for you.

Dave Plowman London SW
To e-mail, change noise into sound.

Alan wrote:
In message ,
wrote
Graham. wrote:

Hi What are the pros and cons of using recharable AA batteries or
a 6V 4Ah
lead acid battery charged by solar power to power a security light?

Janice

For starters AA rechargeable are less than 0.3Ah
but I suspect I am missing something here...

All the rechargeable AA batteries I have are way more than 0.3Ah,
even my oldish ones are 1800mAh which is 1.8Ah. I have lots of new
ones which are 2700mAH, that's 2.7Ah. OK, it's less than 4Ah but I
bet that 4 (or possibly 5) AA cells are smaller than the Lead Acid
battery.

Surely it depends more on the light output from the LEDs vs the 10W
halogen bulb for the application rather than the battery technology?

An expensive 3 or 5W LED is hardly bright enough for a security light.
It may give enough light to illuminate something the size of a small
patio just to the extent that you will be able to see what is there
and not fall over it.

I've got one of those B&D Lightsticks with 21 LED's. Great in a cupboard or
under a sink, but nothing like bright enough for a security light.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

On Wed, 31 Dec 2008 00:53:33 +0000 (GMT), Dave Plowman (News) wrote:

I'm not sure why there was a fashion for those lead acid handlamps.
Ni-Cads etc are lighter and smaller. Perhaps something to do with
voltage/capacity.

Voltage/capacity/size I suspect. D size NiCds are only 4Ahr, the 6v 4Ahr
SLA in my BFO lamp is smaller than 4 x D cells and is easier to
connect/assemble being just a block.

Might be different now, I see CPC have industrial D size NiMH at 10Ahr at
only £9.83 each or 7Ahr at £8.82 each (+ VAT). Consumer rarely get above
3Ahr but I see a 11Ah "Powerex" twin pack for only £16.45. Hum, perhaps
cost comes into in a bigger way a 6v 4Ahr SLA costs about a tenner...

--
Cheers
Dave.

Dave Plowman (News) wrote:

I've one of those 500 candlepower spotlights with a gel batterry in it.
As it needs a new battery is there a better repalcement than lead acid?

Crikey - hope it's a bright night if only 500 candle power. ;-)

Yes I meant 500k!

With most of these things a complete new one costs less than a replacement
battery.

I've been given a couple and inherited this one, it's ok for about 30
seconds! As you say it's not worth replacing the battery.

Dave L says the batterry is 60 Whr to full dod, so maybe 30 Whr usable??

Anyway with the lead acid being 800 grams and Nimh rechargeable 2500 mA AA
cells weighing 35 grams and 1.25V it looks like I only need 10 for the same
performance and only half the weight or are my sums wrong.

AJH

Dave Liquorice wrote:
On Wed, 31 Dec 2008 00:53:33 +0000 (GMT), Dave Plowman (News) wrote:

I'm not sure why there was a fashion for those lead acid handlamps.
Ni-Cads etc are lighter and smaller. Perhaps something to do with
voltage/capacity.

Voltage/capacity/size I suspect. D size NiCds are only 4Ahr, the 6v 4Ahr

They *used* to be only 4Ah, you can now get at least 7Ah in a D size
and probably more.

SLA in my BFO lamp is smaller than 4 x D cells and is easier to
connect/assemble being just a block.

Might be different now, I see CPC have industrial D size NiMH at 10Ahr at
only £9.83 each or 7Ahr at £8.82 each (+ VAT). Consumer rarely get above
3Ahr but I see a 11Ah "Powerex" twin pack for only £16.45. Hum, perhaps
cost comes into in a bigger way a 6v 4Ahr SLA costs about a tenner...

Ah, you've noticed that D cells have increased capacity now! :-)

As you say they are rather expensive, I suspect that the market for C
and D cells is quite small nowadays, *everything* runs on AA and AAA.

--
Chris Green

In article ,
wrote:
As you say they are rather expensive, I suspect that the market for C
and D cells is quite small nowadays, *everything* runs on AA and AAA.

Sub C is the common one for power tools. If only they were so cheap
outside the factory.

--
*A conscience is what hurts when all your other parts feel so good *

Dave Plowman London SW
To e-mail, change noise into sound.