Idiot's guide to a self build battery

[Fintray]

Another small (but time consuming) step, BMS cables extended and individually fused.

[Joeboy]

Nice looms, save a lot of time down the road with the marking up.

[Saladin]

Blimey that's impressive.

I thought I was the only one who fused balance leads. I've never seen a professional original equipment manufacturer do it.
The resistance across friction fit blade fuse holders will not be equal due to the massive manufacturing tolerences. Blade fuses themselves are also extremely inconsistant in terms of resistance and rupture current.
I did exactly the same on many a build except using blade fuseblocks instead of inline holders. I've often wondered if it made a difference to the balance circuit.

Not one I've noticed to be honest. I use active balancers too and resistance is fultile when the balance current is mA or less..My cells are generally pretty consistent.

Noice battery. Proper.

[Joeboy]

Blimey that's impressive.

I thought I was the only one who fused balance leads. I've never seen a professional original equipment manufacturer do it.
The resistance across friction fit blade fuse holders will not be equal due to the massive manufacturing tolerences. Blade fuses themselves are also extremely inconsistant in terms of resistance and rupture current.
I did exactly the same on many a build except using blade fuseblocks instead of inline holders. I've often wondered if it made a difference to the balance circuit.

Not one I've noticed to be honest. I use active balancers too and resistance is fultile when the balance current is mA or less..My cells are generally pretty consistent.

Noice battery. Proper.

Saladin, Welcome onboard, your exuberance is outstanding

[Saladin]

Thanks for the kind words Joeboy,

Don't let my postcount fool you, I've been at this craic for decades. I went monk-mode for a coupla years and realised that no man-solo is going to change the world the amount we need to pull our socks up. It will take community.
I'm building omni-directional frequency controlled micro grids and end user installations with backfeed as a side project. I've 4 harmonised systems running in the workshop at the moment. ~17kVA and a mix of 16kWh Lead acid + LFP combined across the sets.
I don't use VTG even though I can. My propulsion batteries are for mobility, I don't want diminishing capacity on those from domestic loads.

Didja know it's illegal to compete financially with the national grid?
Decentralisation is the future in my opinion. We can trade in energy, calories, services or goods. Fortunately the powers that oppose such developments are blindsided by currency.

I wonder have you come across this resource on LFP? It's the best info on LFP on the net in my opinion.
It also explains how to manage the memory effect that that chemistry exhibits, which most vested interests try to sweep under the carpet and pretend isn't an issue. It is. I've measured it.

[MrPablo]

Yet more DIY batteries in the pipeline!
I've just ordered a set of cells and BMS from Colin, planning to double my capacity as hopefully I can shift energy away from gas usage.

I'm also helping a friend replace his pylontech stack with 2 DIY batteries - the extra capacity for the money is a no brainer.

Looking forward to getting the delivery later this year, thanks again Colin!

[Colin Deng]

Yet more DIY batteries in the pipeline!
I've just ordered a set of cells and BMS from Colin, planning to double my capacity as hopefully I can shift energy away from gas usage.

I'm also helping a friend replace his pylontech stack with 2 DIY batteries - the extra capacity for the money is a no brainer.

Looking forward to getting the delivery later this year, thanks again Colin!

Thank you Paul for the support
It will be ship out soon, just need to wait for the BMS arrived
Battery will be soon ready

Thanks
Colin

[Richard77]

Hi....

I'm considering getting two ready assembled cased 15kwh batteries from Colin. They will be housed in the detached garage.

The garage is single skin concrete block. Metal roof tiles. It will have an insulated roller shutter garage door on it (eventually!). No insulation inside the garage. (Picture below)



Was contemplating getting a heated function added into the batteries in case the temperature in the garage affects the batteries performance/longevity.

Has anyone got any experiences with cold winter months in northern england and whether the batteries performance is affected if left in uninsulated building?

Option 1: insulate garage, no heated function added to batteries.
Option 2: don't insulate garage, add heated function to batteries.
Option 3: don't insulate garage, no heated function added to batteries and don't worry about it.

What option do you recommend?

Was also thinking of putting a few solar panels on the garage roof. It's a low pitch (approx 12°) south facing. Usable space on each side of roof is about 5.5m x 1.6m (shame it would struggle to fit panels vertically)? So maybe 3 horizontally each side and 6 total? Dunno if it would be worthwhile though.

Thanks for your help... Much appreciated.

[resybaby]

Have my Pylontechs in a self made wardrobe looking type of enclosure in my garage, no hearing or insulation but im down in Cornwall so rarely very cold. Coldest my batteries have dropped to is 12c.
Have seen a few people on the Net use celotex type PIR to make a boxing for batteries, so might be worth exploring that as another option?

[Richard77]

Have my Pylontechs in a self made wardrobe looking type of enclosure in my garage, no hearing or insulation but im down in Cornwall so rarely very cold. Coldest my batteries have dropped to is 12c.
Have seen a few people on the Net use celotex type PIR to make a boxing for batteries, so might be worth exploring that as another option?

Thanks....definitely a creative idea and one worth looking at. Would have to be a temporary enclosure I presume though, otherwise would risk overheating them when it's warmer?