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Watt the fμck?
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Monkeh:

--- Quote from: AVGresponding on October 01, 2022, 07:40:59 am ---Looking at the datasheet for the product you linked, they have done exactly what I said; used a lower discharge current to exaggerate the capacity.

--- End quote ---

No they haven't. Read it again and note that both are using standard discharge time curves - 20hr. 350mA for the 7Ah, 450mA for the 9Ah. Also note that the 9Ah weighs 25% more than the 7Ah.
PlainName:
I like to turn nearly everything off in my office overnight, so I arranged to switched spur that provided power for the PC, monitor, Dymo, remote TV monitor, desk lights, etc. Shut down the PC then flick the switch and it's all good, except that after a lot of switching the switch would fail. Replaced, repeat.

My solution was to use an "E-ON Energy Saver Power Down Plug Surge Protect... you get the idea". This is a long time ago, and amazingly you can still buy them:

https://www.amazon.co.uk/dp/B00VKU57D4

The idea is you plug the thing you will be turning off (in my case the PC, but often a TV or something) in the monitored socket, and everything else (that is, what you want to also turn off) in the other. When the power being sucked through the monitored socket drops to some low figure, the entire thing powers down. There's an IR doobrey so you can use you remote control to bring it all back up, but it has a button built in, which is what I use. Says it uses 0.5W in standby but I haven't measured it - my sole purpose was to save me switching loads of stuff individually.
AVGresponding:

--- Quote from: Neper on October 01, 2022, 01:00:33 pm ---
--- Quote from: AVGresponding on October 01, 2022, 07:40:59 am ---I am familiar with the Power Sonic brand, and consider them to be one of the budget brands, they are in no way a premium brand.
--- End quote ---

What about Yuasa? Panasonic don't seem to make lead gel batteries anymore. Any other brand you'd be able to recommend?

--- End quote ---

Are you sure? They seem current to me (ooops, sorry, unintentional pun).  https://industry.panasonic.eu/products/energy-building/batteries/battery-cells/secondary-batteries-rechargeable-batteries/valve-regulated-lead-acid-batteries#please-find-more-valve-regulated-lead-acid-batteries-here-paragraph-1322

I'm not saying Power Sonic are bad, just that they aren't premium (actually they seem to have improved a lot). Any brand that the likes of RS, Digikey etc sell that are in the same-ish price bracket will be perfectly adequate, just that if you use them in a high demand situation like a UPS you aren't going to get the sticker capacity.

Yuasa are good, CSB, Haze, Fiamm. Premium for me is the likes of Hawker/EnerSys. For a home UPS there's no reason to spend that much though. Better to just make sure the float voltage the UPS is charging at is not excessive, and the case temperature is reasonable.
AVGresponding:

--- Quote from: Monkeh on October 01, 2022, 01:23:42 pm ---
--- Quote from: AVGresponding on October 01, 2022, 07:40:59 am ---Looking at the datasheet for the product you linked, they have done exactly what I said; used a lower discharge current to exaggerate the capacity.

--- End quote ---

No they haven't. Read it again and note that both are using standard discharge time curves - 20hr. 350mA for the 7Ah, 450mA for the 9Ah. Also note that the 9Ah weighs 25% more than the 7Ah.

--- End quote ---

That implies they've filled the "free-space" with plate and electrolyte. That would have a knock-on implication for the lifespan, as that would mean there's less space for the H2 to expand into during charge, so it would vent and be lost more easily.
Monkeh:

--- Quote from: AVGresponding on October 01, 2022, 03:11:19 pm ---
--- Quote from: Monkeh on October 01, 2022, 01:23:42 pm ---
--- Quote from: AVGresponding on October 01, 2022, 07:40:59 am ---Looking at the datasheet for the product you linked, they have done exactly what I said; used a lower discharge current to exaggerate the capacity.

--- End quote ---

No they haven't. Read it again and note that both are using standard discharge time curves - 20hr. 350mA for the 7Ah, 450mA for the 9Ah. Also note that the 9Ah weighs 25% more than the 7Ah.

--- End quote ---

That implies they've filled the "free-space" with plate and electrolyte. That would have a knock-on implication for the lifespan, as that would mean there's less space for the H2 to expand into during charge, so it would vent and be lost more easily.

--- End quote ---

Perhaps so. In many applications these are one-shot packs anyway, one real discharge and they've had it, so it may as well be a nice deep one.
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