Greetings from Sweden


Feb 20, 2017
Hi everybody,

I'm a city dweller that for a long time have planned anoff grid cottage to spend a week innow and then. Started picking up and old laptop cells at the recycling center a few months ago when I had a lot of business going there to get rid of the excess stuff we've gathered though out the years and now was moving to a new apartment. Now sitting here with some 160 cells averaging 2Ah.

The plan is to start with 7s20p, run them at3.3v-4.0v, maintenance charged using a 20W panel while I'm not around (there will stillbe some minimal load from some low power electronics so I don't want to shut it down) and a 250W panel when I'm there. According to my calculations this would mean some 0.5kWh available daily in the batteries when charged.The 250W panel should produce about 1kWh perday March-September, while the 20W produce some 20Wh per day during October-February with a lowdip to 10W around the new year. I think it should work out just fine for now,enough to light up the cottage up, get music and be able to work on my laptop most of the day. We'll see if that works out once I get it in place. Might have toexpandto 7s40p,but Ihope myeconomy allows for switching to LiFoPO4.

Also been fiddeling with small DYIwind turbines,steam tubines andpeltier generator for backup.

But for now I'm focusing onan as safe as possible18650 pack.


Staff member
Oct 8, 2016
What part of Sweden? :) Greetings btw.

Im from Smland.