Hello guys. My name is Catalin and i'm on my way to build a powerwall (more of a powershed at the moment) in my hometown Craiova (RO).
Couple of years ago I've got an Opus C-3400, decided to start testing and sorting 18650 cells. I had an idea about what I want but not very sure how to do it, so it was more of a side project, untillast year, when i found Pete's hbpowerwall channel on youtube and a lot of things start to clarify soon after.
My target is a 48V system, PIP and Batriumbased, startingwith a 1kw solar array and adding a wind turbine as soon as the initial setup proves to be stable (and of course more solar panels to be added at a later stage).
Now, for the battery packs. I'm planning to have a 14s40p for a quick start, adding morebatches of 1440p packs in the process until i reach 14s120p. The main issue with this is cell availability, considering the fact that my city is not that big or economically important to be able to finda considerable amountof laptop batteries. Thing are looking even worse when i put in balance the fact that i work in a computer repair shop and I already went through my supply of dead battery packs. More or less, i have around 150 tested cells, with400+ more untested and around 50 more packs on the way. From those tested cells, 30-35 percent are dead, failed the self discharge test or under 1500 mAh (under 1500 go directly to my "other projects" bin). The "good" ones are from 1500 to 2500 mAh (according to Opus).
And here is where i really need your opinion. I am consideringusing everything over 1700 mAh and 75% capacity left,at least until i will havea more consistent flow of cells coming in. I see most of you don't use cells under 2000 mAh, but i cannot afford this luxury for now. In this first stage, the bank will not be pushed hard (mostly because of the initial 40p layout), probably around 500-700w constant draw, with computers, TVs and led lights as load (no inductive motors or anything with high inrush current).
Do you see any majorproblem with using those1700-2000mah cells?
Couple of years ago I've got an Opus C-3400, decided to start testing and sorting 18650 cells. I had an idea about what I want but not very sure how to do it, so it was more of a side project, untillast year, when i found Pete's hbpowerwall channel on youtube and a lot of things start to clarify soon after.
My target is a 48V system, PIP and Batriumbased, startingwith a 1kw solar array and adding a wind turbine as soon as the initial setup proves to be stable (and of course more solar panels to be added at a later stage).
Now, for the battery packs. I'm planning to have a 14s40p for a quick start, adding morebatches of 1440p packs in the process until i reach 14s120p. The main issue with this is cell availability, considering the fact that my city is not that big or economically important to be able to finda considerable amountof laptop batteries. Thing are looking even worse when i put in balance the fact that i work in a computer repair shop and I already went through my supply of dead battery packs. More or less, i have around 150 tested cells, with400+ more untested and around 50 more packs on the way. From those tested cells, 30-35 percent are dead, failed the self discharge test or under 1500 mAh (under 1500 go directly to my "other projects" bin). The "good" ones are from 1500 to 2500 mAh (according to Opus).
And here is where i really need your opinion. I am consideringusing everything over 1700 mAh and 75% capacity left,at least until i will havea more consistent flow of cells coming in. I see most of you don't use cells under 2000 mAh, but i cannot afford this luxury for now. In this first stage, the bank will not be pushed hard (mostly because of the initial 40p layout), probably around 500-700w constant draw, with computers, TVs and led lights as load (no inductive motors or anything with high inrush current).
Do you see any majorproblem with using those1700-2000mah cells?