Ok, so I have a limited experience in this matter and I'm facing a bit of a problem:

I have a defibrillator that uses a set of NiMH rechargeable batteries of size "SC" (diameter 21 mm, length 43 mm) with a voltage rating of 1.2V and current rating of 2.8 Ah. This set needs changing, so I've done my search and could only find NiMh SC batteries with a voltage rating of 1.2V and current rating of 2.5 Ah. The higher current rating ie 4 Ah is only available for NiMH batteries of size "C" (diameter 25 mm, length 49 mm), which I can't use simply because they don't fit in the alloted space and the batteries have to be present onto the machine (portable with the machine) and cannot be located outside for safety issues (high discharge currents). I know that the ones of current rating 2.5 Ah can be used but it will lead to a slow start and will not last as long as the ones with a rating of 2.8 Ah. My question is: How long is the power-up delays? How much will my selection of 2.5 Ah batteries instead of 2.8 Ah batteries affect the performance of my machine? Mind you, at some options the discharge time of the paddles cannot be longer than 25 ms, and the typical situation is a discharge time of no longer than 15 s (standards AAMI ES1-1993 and IEC61010-1-1). Suggestions?
@Xserver: If they had datasheets, I wouldn't be facing this problem :s They're chinese NiMH batteries, so no datasheets. Guess I should just build the battery and test the system with a defi tester.
I suggest you order them online. Defibrillators are common, no ? They wont really miss it. those Chinese batteries will die quickly. but they would surely work for a limited amount of time .
J4D wroteI suggest you order them online. Defibrillators are common, no ? They wont really miss it. those Chinese batteries will die quickly. but they would surely work for a limited amount of time .
Not all defibrillators work with the same type of batteries, or current rating for that matter, but one thing I'm pretty sure of is that about 85% of them operate on Chinese batteries. They will die quick (no doubt about that), but it doesn't matter since whether they die or not they have to be changed every 4 years otherwise it gets banned by the ISO board to be used. Plus, this forces hospitals to buy stuff from our company, is that a bad thing? ;)

Ordering them online means they will arrive in a month or so; defibrillators cannot be held back that long a period of time. They're the soul of any hospital, and every department should have one on standby in case of "Code Blue" on their floor.

I'm constructing the battery from a set of NiMH SC 25000 mAh batteries, run the defibrillator PM tests with a defi tester, and verify whether the defibrillator is fit to be used or not. If so, then yahoo. If not, I'll go with the size C batteries and wedge them somehow into the machine (even if I had to construct an external chamber onto the machine).
mesa177 - since it is mission critical equipment, make sure you test it in stress environment. Especially at lowest and highest operating temperature ranges.
One company where i was worked had special temperature box for testing parts of equipment and whole solution.
The assumption that Chinese batteries will die quickly is false.
All batteries are made in china, you have excellent, good, average,bad quality batteries.
it is up to you to choose!
a month later
I'm looking for this battery: Cyclon 2V 2.5Ah D size sealed lead-acid:



or an alternative for it. Higher current rating is not a problem, but the alternative battery shouldn't differ by more than 3 mm in diameter or 2 mm in height.

Also, I'm looking for 1/2D 1.2V 2.5Ah Ni-Cd rechargeable batteries (with tags):

http://www.ekt2.com/ekt/imgView.asp?idProduct=214024

Katranji won't be getting them anytime soon, so suggestions for places where I can find such batteries are welcomed.
try boujikian at dora, but katranji is the best so if he doesn't have them, no one else got them
mesa177 wroteI'm looking for this battery: Cyclon 2V 2.5Ah D size sealed lead-acid:
Yum :)
@jadz: Spot on, found the Cyclon 2V 2.5Ah battery at Boujikian for 12$ a piece and he did a discount for me (cause I'm so cute :P) and got them for 10$ a piece. Katranji would have sold them for 25$ a piece, I'm so happy :)
mesa177 wrote@jadz: Spot on, found the Cyclon 2V 2.5Ah battery at Boujikian for 12$ a piece and he did a discount for me (cause I'm so cute :P) and got them for 10$ a piece. Katranji would have sold them for 25$ a piece, I'm so happy :)
Glad you found what you were looking for and for relatively cheap!
a month later
And yet 2 more batteries which I'm having trouble finding.

The first used to be available at Katranji, but it's been 4 months and they still haven't got them. I tried searching for them at Boujikian, Bayalian, Yuasa, and three more electronic shops in Dora but no success. I also tried a shop in Msharfieh. It's a 12V 2.3Ah lead-acid battery with both terminal plates located on one side (generally used for cameras):



The second proves to be even more tricky, and I haven't found it neither at Katranji nor the series of the Dora shops. It's an 8V 3.2Ah lead acid battery:



If someone knows a battery shop which has a wide range of lead acid batteries, please let me know.

Thanks in advance :)
I was at Bujukian a few minutes ago and saw someone buy one of these, the small one was for 5.5$ and the big for 15$
AvoK95 wroteI was at Bujukian a few minutes ago and saw someone buy one of these, the small one was for 5.5$ and the big for 15$
:/ I was there today, Jean told me that both models are not supplied by his shop. Which model were you talking about?
mesa177 wrote
AvoK95 wroteI was at Bujukian a few minutes ago and saw someone buy one of these, the small one was for 5.5$ and the big for 15$
:/ I was there today, Jean told me that both models are not supplied by his shop. Which model were you talking about?
Sorry, the batteries I saw were very similar to the ones you posted , the first model you posted turned out to be a similar kind which the poles are the top, and the other battery I thought it was a UPS battery LOL