DIY Battery Pack/Wall

[Lishfish]

Hey everyone,
doing a little side project (have been on and off for a while) where I use 18650 Battery Cells to create a large battery to power your house and or appliances/gadgets so I thought I'd do this thread for those that would like to stay in the loop. EDIT: I will be charging them via 12v solar panels

Last year I managed to source a whole bunch of good cell (think like 300 or so) and suddenly no one wants to give them to me, I currently on the hunt for old/ dead laptop batteries or even old drill ones too, so if you have some (even 1 or 2) lying around hit me up!

So the plan is to make a 12v battery out of 18650 cells wired in both parallel and series, maybe around the 4kw mark? I guess we will see. Stay tuned for more

 

[AAH]

Running a higher voltage will reduce power losses due to current. I wouldn't run less than 24V for that sort of power rating and I'd seriously consider 48V.
Having mismatched cells can mean that there is excessive current in and out of specific cells. If the amp hour rating varies due to different initial ratings or age/use of the cell then the better cell can end up providing much higher current than the dodgier cells.

 

[Goliath]

There's oodles of videos on Youtube about this sort of thing. Some of the info on early videos in a series may be dodgy, as the vlogger has learnt from his mistakes. I think one lesson learnt was to limit the amount of current any cell/group of cells can deliver, generally through some sort of fuse. Uncontrolled current and a shorted cell can make a very nasty fire.

 

[the grinch]

Yeah was thinking yesterday sounds dangerous !
But on a happy note our government is giving away rebates for batteries for solar systems !
Maybe a safer option !

 

[Lishfish]

the other thing I forgot to mention is that the sytem will run through an inverter (12V DC to 240V AC)

 

[Lishfish]

Having mismatched cells can mean that there is excessive current in and out of specific cells. If the amp hour rating varies due to different initial ratings or age/use of the cell then the better cell can end up providing much higher current than the dodgier cells.

Yeah this makes sense, have been looking at sourcing new cells cheap

 

[Lishfish]

There's oodles of videos on Youtube about this sort of thing. Some of the info on early videos in a series may be dodgy, as the vlogger has learnt from his mistakes. I think one lesson learnt was to limit the amount of current any cell/group of cells can deliver, generally through some sort of fuse. Uncontrolled current and a shorted cell can make a very nasty fire.

Yeah have been on jehugarcia and HBpowerwall's Youtube channels. Learnt quite a lot. Thinking of fusing every cell + a bms for each cell as well

 

[Lishfish]

Yeah was thinking yesterday sounds dangerous !
But on a happy note our government is giving away rebates for batteries for solar systems !
Maybe a safer option !

this would be great if we owned the house/s. However I dont think theyd just leave it somewhere unmounted