There is a trend at the moment (mostly US / AU) that people are interested in storing energy (search FB groups) coming from their solar panels / windmills.
But also in certain area’s… where people know they are out of electricty when a hurricane strikes.
There you see these kind of ‘energy suitcases’ … professional but also DIY
Filled with battery’s and an inverter, sometimes solar chargeable too.
Problem is that you need a lot of battery’s (and know what you’re doing!)
If you can afford it you buy a used TESLA battery pack (U$1400)
or a bunch of new NCR 18650’s … but many DIY are using recycled (but still good and capacity tested) battery’s for 1/4 of the new price.
For example, battery packs from electric handtools… if the battery doesn’t work they end up at a dumpster somewhere.
If you open them in many cases there’s only one bad cell… the same is to say for laptop battery packs.
So what they do is sort them on capacity.
First discharge them completely and then charge them… let them rest for a month and measure the self discharge…
Then some rewrap them in a new plastic and use/sell them.
If you create a battery pack with these used cells you make sure you match the capacity because you connect a few paralell (with a battery management system or BMS)
building these packs is a form of art
also you see interesting developments… like stackable 3d printed battery ‘drawers’.
just some more pics (yes I’m interested )
So where comes the LoRaWAN ?
Well… what they do is monitor each cell (barium) and good systems shut down a pack when there’s something wrong.
My idea is to try todo that over LoRaWAN … so wireless monitoring of powerwalls / energy backup suitcases.
russian LiPo test LAB