Hi from Portugal

Hi!

I'm Cesar from Portugal.
For about 1 year, i'm studying PV energy and panels, intending to use them as clean energy source for my home.
But, just like Elon said on powerwall presentation, this type of energy has one big problem... we dont have sun at night

That problem made me search for energy storage systems/methods!
Lead acid is one of the cheapest ways... Lithium one of the most expensive!

So... why not using old laptop batteries and build some kind of powerwall, just like many people around the world
On one of those internet "travels", found HBPowerwall .. and from that youtube channel, i found this forum...

I'm trying to build a very small powerwall style storage system from around 300x 18650 lithium ion cells, removed
from near 50 laptop batteries (no cost on that).
At this moment i'm on that time consuming step of charging and discharging to get the remaining capacity of each individual cell!

Will try to use only those cells that have more than 1500mAh capacity to build 7 blocks in series of 40 cells in parallel (24V system).
Will add one or two 250W PV panels and one MPP Solar PIP-2424.
This system will be my first experiment and the power source for my home light circuits (indoor and outdoor) and some low power loads.
If i like the final results.. i will continue to upgrading it in the future
If not... at least i learned something with it

Regards,
Cesar

Perhaps you could build a small pack with the low capacity cells, test your design and construction skills before starting on the 1500mAh or higher cells.
Most of us are using 1800mAh or 2000mAh as the minimum.

station240 said:

Perhaps you could build a small pack with the low capacity cells, test your design and construction skills before starting on the 1500mAh or higher cells.
Most of us are using 1800mAh or 2000mAh as the minimum.

Click to expand...

Forgot to mention that i'm from electronics area, so... soldering, wire, batteries, copper, etc are my work

My big doubt on this approach is how much time will last an energy storage system like this (with used batteries)... 1 year? 2 years? more?
And how much capacity i will lose over time... until be useless!