diy battery, nissan leaf gen3 cells

[knighty]

I found some Nissan leaf cells on Facebook, bought 72x gen1 (brand new never used) cells from the guy pretty cheap

Talking to him, he does battery swaps on cars for a living, has supplied loads of cells to people making home battery storage, has some bms setups etc. etc.

Went to see him again about more cells, bms etc. there's no more gen1 cells... but he's going to swap my 35kwh of gen1 cells for 40kwh of gen3 cells for free, then supply me a load more gen3 cells

Going to build a 100kwh pack to start with, will add more cells later if needed - it's hard to tell what I need, I don't have the solar or the heat pumps yet!

I'll add photos when I get the cells

Was going to cad design some busbars and have them laser cut but struggling to fine the dimensions I need online, might have to wait till I have the cells to measure them, I'm a bit worried about compounding errors, first few cells might be ok but once I have a stack 10 high I could be miles off

There's an old workshop in the garden (just moved 3 months ago) we're going to knock that down and rebuild it (it's knackered anyway) - plan is to build it better for solar to cover it in panels and put the batteries in there too - measuring it on google earth it's 16m long and 5m wide, a bit like a normal garage but long, my thinking is to extend the roof down towards the ground (see crude diagram)



It'll be more than 3 meeters away from any boundary so I think I don't need planning permission? - might go for it anyway to extend it as large as possible


I'd rather spend cash on solar/batteries/heat pumps than on oil, burning 250litres/week right now!

I'll add more photos when I'm home :-)

[Stinsy]

Sounds like a good project!

What are you going for WRT pack voltage? Up until recently 48V was standard, nowadays you can get so-called "High Voltage" (don't get me started) inverters that work from 80-480V (or similar).

Are the LEAF modules you're getting 2S or 3S? Does their connector expose each cell for balancing?

[Countrypaul]

Have you read the other thread? https://camelot-forum.co.uk/phpBB3/view ... 168#p55168

Particularly section 6.5.7 "The total stored energy of all units in an individual dwelling house shall not exceed:
a) 80 kWh where batteries are installed in one of the following locations:
1) detached garage or outbuilding;
2) outdoors (ground-mounted or wall-mounted); or
3) attached garage or outbuilding that has a fire separation with a performance of at least
REI 60 to BS EN 13501 series (60 min to BS 476 series for loadbearing capacity, integrity and
insulation); or
b) 40 kWh in all other cases."

Not sure what that means if you put a car with a 100kWh battery in your garage though. Maybe it could only be 80% charged

[knighty]

Sounds like a good project!

What are you going for WRT pack voltage? Up until recently 48V was standard, nowadays you can get so-called "High Voltage" (don't get me started) inverters that work from 80-480V (or similar).

Are the LEAF modules you're getting 2S or 3S? Does their connector expose each cell for balancing?

models I'm getting are 4s, but there's really 2s+2s and can be reconfigured to 2s2p pretty easily so I'll do that, it'll make it much easier building the pack
(guess they're more than 2p really because each 2s pack is already a few in parallel, not sure how many)

sticking with 48v, happy working with that... not at all happy with high voltage DC - I've done plenty of 3 phase stuff etc. in my time and doesn’t bother me at all, I'm a bit clumsy, not keen on the whole get a DC shock tense up and can't let go till you're dead thing :-o

[Stinsy]

Sounds like a good project!

What are you going for WRT pack voltage? Up until recently 48V was standard, nowadays you can get so-called "High Voltage" (don't get me started) inverters that work from 80-480V (or similar).

Are the LEAF modules you're getting 2S or 3S? Does their connector expose each cell for balancing?

models I'm getting are 4s, but there's really 2s+2s and can be reconfigured to 2s2p pretty easily so I'll do that, it'll make it much easier building the pack
(guess they're more than 2p really because each 2s pack is already a few in parallel, not sure how many)

sticking with 48v, happy working with that... not at all happy with high voltage DC - I've done plenty of 3 phase stuff etc. in my time and doesn’t bother me at all, I'm a bit clumsy, not keen on the whole get a DC shock tense up and can't let go till you're dead thing :-o

Don't kid yourself that 48V is in any way "safe". The dangers are just different! Drop a spanner across the battery terminals and you'll get a face full of molten steel!

[knighty]

Have you read the other thread? https://camelot-forum.co.uk/phpBB3/view ... 168#p55168

Particularly section 6.5.7 "The total stored energy of all units in an individual dwelling house shall not exceed:
a) 80 kWh where batteries are installed in one of the following locations:
1) detached garage or outbuilding;
2) outdoors (ground-mounted or wall-mounted); or
3) attached garage or outbuilding that has a fire separation with a performance of at least
REI 60 to BS EN 13501 series (60 min to BS 476 series for loadbearing capacity, integrity and
insulation); or
b) 40 kWh in all other cases."

Not sure what that means if you put a car with a 100kWh battery in your garage though. Maybe it could only be 80% charged

I just saw that moments ago

I'm planning on some sort of enclosure for the batteries, they'll be 150ft away from the house and there's nothing around the workshop that’ll burn so I'm happy there

not sure how to make the pack acceptable to the powers that be - you'd assume a suitable container(s) would meet the regs

Once they're in use I could quite well need more capacity

I could put 80kwh in the workshop and and then more in the garage (also detached)... but I guess that'll make it all a bit complicated

I was tempted to get a 20ft container dropped on the foundation and then build the rest of the workshop around it to use it to store batteries/inverters, help keep them clean/tidy/dry

[knighty]

Don't kid yourself that 48V is in any way "safe". The dangers are just different! Drop a spanner across the battery terminals and you'll get a face full of molten steel!

I've replaced a few 48v forklift battery packs one heavy 2v cell at a time, tools wrapped in tape when I can;t find the insulated stuff etc.

I'm not really scared of electric shocks, had enough in the past from 240v... it's just my kind of luck I'd die from a 300v dc battery pack so I'd rather avoid it!

Once I have the dimensions figured out I#'ll 3d print some terminal/busbar covers for the packs, help make them safer

[richbee]

I found some Nissan leaf cells on Facebook, bought 72x gen1 (brand new never used) cells from the guy pretty cheap

Talking to him, he does battery swaps on cars for a living, has supplied loads of cells to people making home battery storage, has some bms setups etc. etc.

Went to see him again about more cells, bms etc. there's no more gen1 cells... but he's going to swap my 35kwh of gen1 cells for 40kwh of gen3 cells for free, then supply me a load more gen3 cells

Going to build a 100kwh pack to start with, will add more cells later if needed - it's hard to tell what I need, I don't have the solar or the heat pumps yet!

I'll add photos when I get the cells

Was going to cad design some busbars and have them laser cut but struggling to fine the dimensions I need online, might have to wait till I have the cells to measure them, I'm a bit worried about compounding errors, first few cells might be ok but once I have a stack 10 high I could be miles off

There's an old workshop in the garden (just moved 3 months ago) we're going to knock that down and rebuild it (it's knackered anyway) - plan is to build it better for solar to cover it in panels and put the batteries in there too - measuring it on google earth it's 16m long and 5m wide, a bit like a normal garage but long, my thinking is to extend the roof down towards the ground (see crude diagram)



It'll be more than 3 meeters away from any boundary so I think I don't need planning permission? - might go for it anyway to extend it as large as possible


I'd rather spend cash on solar/batteries/heat pumps than on oil, burning 250litres/week right now!

I'll add more photos when I'm home :-)

I think there's a requirement for building regs approval above 25m squared.
Permitted development is usually allowed up to 50% of the original land area (I think)