Hello guys,
I have been watching a lot of videos and reading posts of you guys building powerwalls. Big thumbs up for you!
I live in Spain, so we get lots of sun around here and I love the idea of green energy. For now I dont dare to build a large powerwall as many of you guys are going but I am happy to start small.
My goal is to run the house lights. I havent measured the real consumption yet, but I reckon it should be something like 750Wh/day or so.
A friend of mine works at a large companies computer helpdesk and she has given me already around 20 laptop packs (two types only). My biggest concern is that the cell inside are prismatic cells :s this makes it more interesting since things are different, but my biggest concern is safety, and I am not very confident about the cells since nobody is using this kind of cells. I have tested almost all and I get between 3000 and 3700 mAh on each cell (yippiee) . The label says 4290 mAh, but I wonder how they really measure it I charge and discharge at 1A with the Imax B6. Probably they get to those values at lower currents.
I reckon the cells are high quality (HP laptop pack, Samsung cells) but I am not sure I will give more details later when I have more time to write, but the cells are quite interesting. The outside metallic case is the positive terminal (odd, isnt it?), they dont have a heatshrink, and they have a little component between cells which happens to be a kind of switch which gets open when there is a short, but then gets back to its original state It is like a short circuit protection implemented with a thermostat. When it gets hot due to the heat, it opens. After a few seconds, it closes. Quite interesting.
I will open a new thread in a few days with pictures so you can see it. I will them explain how I am planning to connect the thing together so you can follow and hopefully give me a hand in the process!
Cheerios!
I have been watching a lot of videos and reading posts of you guys building powerwalls. Big thumbs up for you!
I live in Spain, so we get lots of sun around here and I love the idea of green energy. For now I dont dare to build a large powerwall as many of you guys are going but I am happy to start small.
My goal is to run the house lights. I havent measured the real consumption yet, but I reckon it should be something like 750Wh/day or so.
A friend of mine works at a large companies computer helpdesk and she has given me already around 20 laptop packs (two types only). My biggest concern is that the cell inside are prismatic cells :s this makes it more interesting since things are different, but my biggest concern is safety, and I am not very confident about the cells since nobody is using this kind of cells. I have tested almost all and I get between 3000 and 3700 mAh on each cell (yippiee) . The label says 4290 mAh, but I wonder how they really measure it I charge and discharge at 1A with the Imax B6. Probably they get to those values at lower currents.
I reckon the cells are high quality (HP laptop pack, Samsung cells) but I am not sure I will give more details later when I have more time to write, but the cells are quite interesting. The outside metallic case is the positive terminal (odd, isnt it?), they dont have a heatshrink, and they have a little component between cells which happens to be a kind of switch which gets open when there is a short, but then gets back to its original state It is like a short circuit protection implemented with a thermostat. When it gets hot due to the heat, it opens. After a few seconds, it closes. Quite interesting.
I will open a new thread in a few days with pictures so you can see it. I will them explain how I am planning to connect the thing together so you can follow and hopefully give me a hand in the process!
Cheerios!