1.000.000 watt hours in a box from Sunsynk ...
well, not exactly a box but a bloody big container !!! wouldnt it be great if they supplied a smaller version that you just hook up to your house, job done!
These look to me like they are 5kWh rack-mount boxes.
So they'll probably have 100Ah cells inside.
I wonder why they've decided to start from a relatively small capacity cell.
You get a better Ah/$ if you use larger cells.
Yes, I realise that a 5kWh box is at the limits of what one person can lift in/out of a rack.
But if you're going to be building the components into a 1MWh container, then you could literally place each larger cell into an open steel shelving system (and use mechanical means to hold them in place of course).
I'm also interested to see that each column/rack is made of 12 battery units in series with a master BMS/monitor/controller in a separate box at the top.
So each column is high-volts and low-current.
That's why the interconnecting power cables look as if they're 25mm² or possibly 35mm², and probably carrying no more than 200A-ish.
Speculating a bit further - if each battery box outputs around 50v DC, then that gives 600v for the column.
If anyone else knows SunSynk's battery range better than I do, then please leap in and correct me.
Save energy... recycle electrons!
Posted by: @transparentIf anyone else knows SunSynk's battery range better than I do, then please leap in and correct me.
Keith has been putting out videos of 3-phase 50kW inverters which run on (up to 2) high-voltage stacks of batteries (with independent power connections for each stack). I guess the 1MWh container is a natural extension of this product line, re-using that family of products. 400kW => 8 50kW inverters, which corresponds to the 8 displays in the inverter compartment, meaning 2 high voltage stacks per inverter.
Posted by: @transparentYou get a better Ah/$ if you use larger cells.
Off-the-shelf component use can reduce development costs, risks and time-to-market, especially if these are in-house components. If it takes off in a big way things will change. Incidentally 16 * 12 * 45kg = 8,640 kg of batteries and the container has a listed maximum payload of 24,480 kg, so at a rough guess less than half the maximum mass of the container is used. Moving to a BYD blade-based battery would triple the capacity, although this would come at the cost of substantially changing assembly and maintenance.
By way of contrast, see

for a 300kWh battery (88kVA in/out) made out of 4 re-used Tesla battery packs. 2.5m * 1.9m * 1.9m and 3 tonnes, so a little awkward for my garden!
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