Re: Battery power for big SSTC

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Original poster: "Black Moon" <black_moons-at-hotmail-dot-com> 

you'll want deep cycle if you want to fully discharge the battery, while 
starter can safty give up to 5~10c, they arnt rated for discharge below 
about 80% or it majorly lowers the cycles.
deep cycle will do 1~5c, and thats still plenty since thats like 300amps 
for a 100CA battery at 3c, but check with the manufacture for datasheets 
about max load. Note that at '1c' rate, it only takes about 1/2 an hour for 
a fully discharge a battery, as the capacity of a battery reduces the 
faster you discharge them. Nicads can also typicaly take extream discharge 
rates, I know C sized nicads used in RC raceing can do 30amps for 5 mins 
(without damageing the battery)


>From: "Tesla list" <tesla-at-pupman-dot-com>
>To: tesla-at-pupman-dot-com
>Subject: Re: Battery power for big SSTC
>Date: Wed, 17 Sep 2003 11:12:40 -0600
>
>Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net>
>
>Actually, you can probably pull a lot more than 60A from that 60Ah
>battery... 200A wouldn't be unusual.. you'd have to watch the heating of the
>battery, though.
>
>If the batteries are engine starting types (car batteries), then they're
>designed for 100% duty cycle at a low current (20 hour discharge) and for
>infrequent gargantuan current (starts at 300A+, but perhaps 30 seconds/hour
>duty ).
>
>Indeed, stringing together a bunch of batteries is a good way to get very
>high powers without depending on mains current.  My "portable" x-ray machine
>power supply originally used 100V of NiCd to put out 100A into the 500Hz HV
>inverter.  Charge for 8 hours on the 115V wall socket, make those 10 kW
>exposures for 100 seconds, etc.
>
>
>----- Original Message -----
>From: "Tesla list" <tesla-at-pupman-dot-com>
>To: <tesla-at-pupman-dot-com>
>Sent: Wednesday, September 17, 2003 6:59 AM
>Subject: Battery power for big SSTC
>
>
> > Original poster: Matthew Smith <matt-at-kbc-dot-net.au>
> >
> > Hi All
> >
> > Inspired by Dan's 10kW SSTC, I was wondering if anyone considered car*
> > batteries** as a power source for larger SSTCs?
> >
> > I am able to get batteries which are not quite good enough to start an
> > engine but can nevertheless hold a charge, for free.  I use a bank of four
> > to run an ex-telecomms inverter - can give 300W for several hours.  This
> > got me thinking...
> >
> > A 60Ah battery can deliver 60A for an hour when new.  When old, we can
> > probably still get 60A, just not for so long.  If we hook up twenty of
> > these 12V batteries, we have 60A -at- 240V = 14.8kW to play with. (Yikes!)
> >
> > Could this be a way of overcoming the limitations of smaller domestic
>supplies?
> >
> > Cheers
> >
> > M
> >
> >
> >
> > * Automobile for those in the USA
> > * I should really call them accumulators.
> >
> > --
> > Matthew Smith
> > Kadina Business Consultancy
> > South Australia
> > http://www.kbc-dot-net.au
> >
> >