Router Battery Backup

[Rickster]

It's rated 75 Wh isn't it?

75/20 = 3.75 hours

So it sounds about right. Your average load was probably more like (75/5.5 = ) 13 W.

(The mAh rating of these things is worse than useless. Capacity depends on a second factor, namely cell voltage, which in this case is apparently 3.125 V. Only use Wh when comparing UPSes.)

Hmmm ok, so that website is talking kak then.

 

[x7razor]

Hmmm ok, so that website is talking kak then.

I use this app when i am lazy doing calculations manually lol. But yes your runtime sounds about right.

 

[Tomtomtom]

Hmmm ok, so that website is talking kak then.

100%. The written formula further down that page is even worse. Not even an AI would hallucinate that.

Working backwards, it seems to assume a voltage of 12 V (i.e. lead acid.) They manage not to state this anywhere.

 

[airborne]

They were junk no-name cells and degraded super fast early on, maybe down to 80% over the first 20 cycles. Then they were held at 100% for a couple of years. This was a replacement for the original battery.

The original didn't do much better and allegedly its cells are Panasonic. But, it's been a more graceful decline, so still usable after 10 years.

I've only got high quality branded cells out of genuine OEM laptop batteries, Samsung/Panasonic/LG etc, most of which were not far off their rated capacity.

 

[Tomtomtom]

I've only got high quality branded cells out of genuine OEM laptop batteries, Samsung/Panasonic/LG etc, most of which were not far off their rated capacity.

If not far off their rated capacity then what was dead about the pack?

One thing I can say is these cells I retrieved were well-balanced... All equally dead.

 

[airborne]

If not far off their rated capacity then what was dead about the pack?

One thing I can say is these cells I retrieved were well-balanced... All equally dead.

Sorry by dead pack I mean from a dead laptop. I used to know a guy that ran a pc repair shop and I’d buy battery packs off him, he always had a whole pile of unrepairable laptops in his storeroom, typically blown motherboards. I was very surprised at how good most of cells were, high quality 18650 cells are remarkably durable.