Nowty Towers DIY Battery Project

[Richard77]

What "officially" is the maximum you can have nowty? Is there any limit to the amount you can have?

There is no space left in the battery cave so I am at the Nowty Towers official limit, this will be my last upgrade for a very long time, maybe ever.

On a practical note, the maximum could be say 75% of capacity you can charge up in a 6 hour cheapslot. I have about 200A max charging capacity so thats probably very close to 75% of my usable capacity. My usable capacity is probably between 80kWh and 90kWh, say its 80kWh, 75% of that is 60kWh. 200A x 50V = 10kW so thats 60kWh in a 6 hr charging slot.

If we get a dull day I might do a capacity test using my VIctron SmartShunt to count the Ah's from full to empty.

Sorry I didn't explain myself properly... I meant is there a maximum capacity you can have at a residential property? Are you still within the "official" limit if there is one?

On a side note... How long before You become Nowty Energy Ltd... ? You could probably start powering some of your neighbours properties not just your own soon!

[nowty]

..................So what cells are they? I make them 315Ah...

From Fogstar again with free delivery, I would have bought the same Envision 280kWh Grade B again as they were £58.46 per kWh but they were sold out, so I bought the Envision 315kWh Grade B, they work out at £65.97 per kWh.

The marked capacity for this batch range from 334.051Ah to 336.855Ah.

I recently bought a battery internal resistance meter, only about £30 from Aliexpress.

Oh the fun,


And I don't know why the cells are grade B,

• They are visually perfect, no bulges, posts are perfect with quality welds, no marks on the plastic covering.

• They were manufactured in December so are less than 6 months old.

• Tested capacity exceeds the nominal capacity.

• Most of the internal resistances I've measured are within the datasheet spec 0.17 +/- 0.05 milli Ohm's, so 0.12 to 0.23 milli Ohms. Most are around 0.20 to 0.23, only a handful are slightly higher around 0.25mOhm or 0.26mOhm.

EDIT - I have just been round the cells again and it does depend on where I measure from, when I'm getting the probes right on the side of the aluminium base of the stud, I'm getting most at around 0.18 / 0.19 mOhm.

[nowty]

What "officially" is the maximum you can have nowty? Is there any limit to the amount you can have?

There is no space left in the battery cave so I am at the Nowty Towers official limit, this will be my last upgrade for a very long time, maybe ever.

On a practical note, the maximum could be say 75% of capacity you can charge up in a 6 hour cheapslot. I have about 200A max charging capacity so thats probably very close to 75% of my usable capacity. My usable capacity is probably between 80kWh and 90kWh, say its 80kWh, 75% of that is 60kWh. 200A x 50V = 10kW so thats 60kWh in a 6 hr charging slot.

If we get a dull day I might do a capacity test using my VIctron SmartShunt to count the Ah's from full to empty.

Sorry I didn't explain myself properly... I meant is there a maximum capacity you can have at a residential property? Are you still within the "official" limit if there is one?

On a side note... How long before You become Nowty Energy Ltd... ? You could probably start powering some of your neighbours properties not just your own soon!

If you mean this thread,
https://camelot-forum.co.uk/phpBB3/view ... =14&t=3619

Obviously not on a number of counts, but I don't "do" official limits, they are whatever they are, and mine are within my own engineered risk boundary.

[AGT]

I got a delivery today too!

[Stinsy]

I got a delivery today too!

How's your back?

[AGT]

Not bad no 1 son unloaded into the drive and I loaded car twice and took it around the back to the garage…

[nowty]

Back and neck ache are stopping play for the day here, but they are now in matched pairs in the battery cave with a little tension on the springs to keep the block all rigid.

"Déjà vu", matching pairs the Nowty Towers way, put them all in sequence from lowest to highest capacity, then take one from the highest end and one from the lowest end to pair up. Rinse and repeat until they are all paired up.



All in now, I had a nightmare when I was a single epoxy sheet separator short. , but found I had doubled up one of them, of course it had to be the last one I checked.

[Joeboy]

Back and neck ache are stopping play for the day here, but they are now in matched pairs in the battery cave with a little tension on the springs to keep the block all rigid.

"Déjà vu", matching pairs the Nowty Towers way, put them all in sequence from lowest to highest capacity, then take one from the highest end and one from the lowest end to pair up. Rinse and repeat until they are all paired up.



All in now, I had a nightmare when I was a single epoxy sheet separator short. , but found I had doubled up one of them, of course it had to be the last one I checked.

That is a sleek looking job Nowty. How many days can you now run OG in Winter? (Nov to Feb).

[nowty]

..................That is a sleek looking job Nowty. How many days can you now run OG in Winter? (Nov to Feb).

Well that is one of the reasons for the capacity increase, if I am to ditch the gas boiler I want to be confident that I can run the heatpumps for heating in the worst time of the year for 1.5 or 2 days. I have not run the gas boiler in anger for around 2 years now but I want to be confident of being OK even if we have a 24hr leccy power cut. The longest we have been without power in the past decade is about 12 hours, we have had a couple of 6 hour outages as well.

The extra capacity increase will also allow significantly more paid export and give me the advantage of running in the summer at say 50% SOC and facilitate loads of charging headroom to reduce the amount of curtailment if we are on holiday. The latest increase in capacity has been cost neutral in that the sale of my 23kWh 7.5 year old Pylontechs have paid for 32kWh of brand new capacity.

Of course I have extra ancillary costs and the pylontechs are possibly the most robust stand alone batteries you can buy.

[nowty]

A midnight busbar fitting frenzy has showed up 3 missing long ones.

I ordered 15 + 3 long busbars off AliExpress, they arrived and I assumed they were all there. It appears the 15 turned up but not the 3 and I assumed they were all in there and confirmed they had all arrived.

It hurts a bit, but under £12 for another 3 including delivery from China in about a week and I can still use the single busbars I have to go operational.