I note in Tony's article a predicted failure mode for this battery is a short circuit. So, we are very lucky so far in that it appears to be open circuit or has developed a high internal resistance. Regarding different battery chemistries that are suitable for the ISS. - I see in some of the videos produced by the crew that there are a large number of commercial cameras on board for Earth observation. Presumably these are powered by conventional Lithium Ion battery packs. Not exactly rated for the job, but it does show there is more than just Silver/Zinc onboard although there could be a maximum energy limit to the capacity to avoid fire / explosion. (e.g. there's a 100W/hr limit to some cubesat launches)
Thanks....and still enjoying ARISSat-1
David G0MRF
-----Original Message----- From: Trevor . m5aka@yahoo.co.uk To: amsat-bb amsat-bb@amsat.org Sent: Sun, 14 Aug 2011 20:54 Subject: [amsat-bb] Re: Thinking about ARISSat-2
--- On Sun, 14/8/11, Burns Fisher burns@fisher.cc wrote:
This obviously requires additional electronics; in particular the battery can't be on the main power bus; we want to be able to isolate it to prevent it charging on every orbit. But that might be good anyway...the ability to isolate the battery might be desirable when the battery does die for good.
Presumably if RSC Energia provide the resources to launch ARISSat-2 it'll be the spare ARISSat that was delivered to Moscow along with ARISSat-1 that will be going up ?
I guess due to it's current location there'd be little opportunity to make changes to the circuitry ?
I've been very impressed by the Slow Scan TV pictures from the satellite. Including SSTV was a good move both in terms of educational outreach and for promoting Amateur Satellites to the wider Amateur Radio community.
73 Trevor M5AKA
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