Battery Question

[Seekscore]

I have the opportunity to purchase some batteries that appear to be in a good clean shape. No corrosion. I think they were removed from an industrial battery backup system. Each battery has 2-2.4v cells for a 4.8v battery. The part# on them doesn't look up to anything I can find on the web. 2x-TLP25. Each one appears to be a lead acid with several plates. Each 4.8v battery weighs 450 pounds. I can get them for $0.25 a pound.

Is my math right in saying that each one is a 437Amp Hours if each is rated 15 minutes at 1750 Amp Hours? If I use 6 of them in series to get 24 volt, does that mean I still have 437 Amp Hours at 24V?

[TomW]

 If I use 6 of them in series to get 24 volt, does that mean I still have 437 Amp Hours at 24V?

Basically that is true. Assumption being they have that capacity.

My 450 AH 24 volt pallet jack battery scales about #1200 I believe. and is in a steel can 13W X 31L X 24 inch tall. From sheer size I think you may have more capacity than the 437 AH as it will scale over 2X what mine weighs. Mine were bought new last February for considerably more than a quarter a pound, too!

Equal batteries in series have the AH of a single battery at a higher voltage.equal to the number of batteries times the voltage of one.

Tom

[scottsAI]

Seekscore,

Search on TLP25;

RAYLITE - M Solar battery:

TLP 25/9S: 4 V, 1000ahr, 102kg, 10.7 L

450lb = 204kg using two above right on. 5 year warranty.

http://www.ecosolar.com.au/Batter.htm (half way down the page)

http://www.rpc.com.au/pdf/RAYLITE%20MSOLAR%20INSTALLATION%20AND%20MAINT.pdf

24v @ 1000ahr battery, used for $675.

Using golf cart batteries: 6v @ 225. Need 4 to get to 900ahr (short a bit)

6v * 4 = 24v; 4 x 4 x $70 = $1,120.

Half the price.

Value depends on how old and how well they were taken care of.

YMMV

Have fun,

Scott.

[Ungrounded Lightning Rod]

IMHO battery backup / UPS systems are a good source of batteries for home RE.  They're kept charged except during outages and tend to be rotated out for new ones when they've still got about 2/3 of their rated lifetime left.  Then they can last longer than rated in home service if you keep 'em properly charged and have enough of 'em so they don't discharge deep - which is easy if you're getting them in power-a-server-farm-for-a-half-hour lots at scrap prices.  B-)

(If a company is paying the big bux to keep a critical load running or shutting it down gracefully in a power outage they're not going to let the batteries get near end-of-life and then have the UPS fail to do its job when needed.  Providing management and the facilities department are on the ball, of course.)

(I'm trying to cut a deal at my day job for the next double-pallet of batteries they rotate out, in a year or two.  The last batch caught me by surprise so I wasn't ready for it.  B-b)

[Boss]

Dang twenty five cents per pound a 450 pounds per battery, I had no idea those big batteries were so spendy\