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Just a few Quick Question's, regarding Capacity and Pack Protections
#1
so Currently i've Built 7x 1s30p Packs Li-Ion packs,

Some Details:
Nominal Voltage per 18650: 3.7v
Nominal Capacity per 18650: 2000mAh
Max Capacity per 18650: 2400mAh

Nominal Voltage Per Parallel Cell: 3.7V
Nominal Capacity Per Parallel Cell 60Ah


Current cable runs are 0.2-0.5 meters max per cable in the pack using 12AWG which is just within the limits on 24V@60A = 12AWG or 10mm² (73A max) according to a DC Cable Sizing tool at solar-wind.co.uk

I'm Building a Batrium Protected pack of 7s30p currently and when I add to the pack i'll add more once I have enough for a 14s30p pack of quality cells.

Currently the system is not in use yet. awaiting Batrium Biggest Starter kit Delivery this week as well as Solar Charge Controller, (Victron BlueSolar 75/15)

and a Basic Reliable 2000W Off Grid Inverter, and i'm trying to make sure i got the Safety Part Correct.

I'll be Limiting Total Battery Discharge to 1C, so with my current calulations i think is either

1s30p = 60000mAh = 1C = 60A
7s30p = 420000mAh = 1C = 420A 

which of the Above Values are correct?

haven't done a initial Discharge test yet as i've not got the BMS yet, but once that shows up this upcoming week, i'll need to be able to setup the Circuit Breakers between Everything correctly.

I'll be putting in a 15A Circuit Breaker between Battery and Solar Charge Controller.
I'll be putting a (2000W/120V = 16.66A) ~15A Circuit Breaker between Battery and Inverter
I'll be putting a small 120V@10A Circuit Breaker on the Inverter Output, for now.
I'll be putting a 60A Circuit breaker between Each Battery in the pack as they might be pushing power Large amounts of power between them for balancing (Guessing here), and 1C is 60A per Parallel Pack

i'll be using a 30v @ 30A DC Power Supply with a 12v relay attached to the Batrium Expansion Board to feed the Solar Charge Controller until i get Solar Panels in Play

I'm trying to be as safe as possible as well as feed my curiosity, currently i don't have fuses on individual 18650's as i'm using the ***** 2.0 battery connector kit for now,

will move to using glass fuses on the negative side once i upgrade to 48V.

any thoughts or opinions on this Idea / buildout would be useful to improve or fix any mistakes.... thanks in advance for anyone that shares there knowledge...

Current Build includes:
BMS: Batrium Watchmon4 with Shunt and Expansion board
Battery Bank: 24v = 7s30p = Current Capacity between 1554Wh & 1722Wh
Charge Controller: Victron 75V/15A
Inverter: 24VDC --> = 120VAC@16.66A = 2000W
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#2
1C = 2.2A per cell as they are 2200mAh in capacity

You don't multiply series connections to increase amps, that's only for parallel.
30 * 2.2 = 66A

If you are putting a 15A breaker between battery and inverter, then you will *not* be limited discharge based on C rating. You'll be limited to the breakers potential.
2000W / 120V does not equal 16A on the battery side. 2000W / 24V = 83.3A on the battery side
60A breaker between each pack?? You mean have 7 breakers for each 24V string? If so, no need. This is a waste of money. You only need "1" 60A breaker between the whole battery and the inverter

I believe you need to do more reading of the threads here to gain greater knowledge of the setup. You are lacking some basic knowledge that you should have before attempting such a task/project. Please read the FAQ and use the search feature on the threads if you want to find something more specific.
Watch HBPowerwalls, DIY Tech & Repairs (aka daromer here on the site) videos to get a more visual understanding of what's going on.


Now, questions for you:
Why 24V 7s setup? Do you already have the equipment for this, or still planning? How much storage do you plan on having? How much/many devices do you plan on running off the inverter(s). I know it's grid-tie, but how much are you going to expand on this, or are you only going to use the 1? What are future plans for the battery storage?
Proceed with caution. Knowledge is Power! Literally! Cool 
Knowledge is Power; Absolute Knowledge is Absolutely Shocking!
Dollar Shave Club. Best Razor I've ever used
Certified 18650 Cell Reclamation Technician
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#3
Thanks @Korishan 

yeah 1C per 18650 is = 2A

i was asking the questing just for clarity really and to assure myself. 

30p * 2 = ~ 60A 

the 15A CB between battery and inverter is for initial Safety while i'm still learning to make sure noone overloads the Packs since the Off Grid 2000W Inverter is way to large at this time and not all that much quality,
i'll be adding more and more Parallel Packs over time current planned is the initial 7s30p for now as that is the battery pack's i've finished building,

i'll upgrade the Inverter and Charge Controller in the future to a INV: to a 48V 12kW with CANBus


Understood on the 7 CB's on the single 24V pack

I'll be putting a (2000W/120V = 16.66A) ~15A Circuit Breaker between Battery and Inverter < yeah i wrote that wrong i was thinging in AC not in DC Fail on my part thinks for that.


Now, questions for you:

Why 24V 7s setup? Cause i've already built the 7x 1s30p packs. and need to get the wifey understanding that it's useful, by giving us useful power during hurricane season this year.


watched every video from HBPowerwall multiple times, also watched Average Joe and Jehu through and through,

but the only way to really learn is to work with it. and test and hypothesize and test agian.


spent the better part of a year learning and thinking and play/test in small scale, i've done years of micro-electronic's in the past and have been working on electronic's in the DC world for +/- 10yr's, just never anything upwards of 24vdc and never more than 10A, but never to late to learn.

i've built a 1s80p pack before but decided to dismantle it for now to work on a smaller scale.

Do you already have the equipment for this, or still planning? Currently i've got the 7x1s30p packs, the Batrium Starter Kit is arriving this week, the Inverter and Charge Controller are also on there way.

How much storage do you plan on having? totally off grid in the Long term future 36kWh, with a 12Kw Inverter but this is kinda an In Case of Emergency Lighting and Basic Small Electronic Use currently incase the hurricane kills grid power in september.

How much/many devices do you plan on running off the inverter(s). I know it's grid-tie, but how much are you going to expand on this, or are you only going to use the 1? What are future plans for the battery storage? it's not grid tie, i'll expand on this 


Current Stage:
Assumptions: 210 18650's made into (1s30p) parallel cells
Voltage: 24V
Stage 01: 7 x 1s30p(60Ah) = (222Wh * 7) = 1.554Kwh

Next Stage:

Assumptions: 420 18650's made into (1s30p) parallel cells

Voltage: 48V
Stage 03: 14 x 1s030p(060Ah) = (222Wh * 14) = 3.108kWh

There are 10 more stages with each adding 420 18650's culminating in the Final stage below.

Final: 
Assumptions: 4620 18650's made into (1s30p) parallel cells
Voltage: 48V

Stage 11: 14 x 1s330p(660Ah) = (2442Wh * 14) = 34.188kWh

i'm in it for the long haul. and it's kinda became a hobby working with the shucking and testing and soldering cleaning moving to more modular packing etc, etc.
I had to go through to get these packs built.
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#4
I would have gone to 48V directly. Going 24V first for learning is just wasting money unless you got the gear. Sad to say that but its true and we see people do it over and over Tongue

Beware of taking your current cells and just creating 14s15p system instead of 7s30p will give you the exact same max output at 1C! Yes it takes 7 more longmons but thats not much of a cust and you will be using it. But it saves you buying 2x inverters and 2x chargers...
Limiting current or such with a fuse is not really limiting but I understand your deal there and I would do the same thing at the inverter side.

Just beware of that a 15A breaker will easily hand out 20 or even 25A for pretty darn long time before it trips Wink Depends on the type of breaker you use.
Korishan likes this post
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Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 83kWh LiFePo4 | 10kWh 14s 18650 |  66*260W Poly
Upcoming: 14S 18650~30kWh | Automatic trip breakers, and alot more
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#5
Ahh, not sure why I thought "grid-tie". Brain must of been stuck on a previous thread Tongue Ok, that' clarifies a little.
Proceed with caution. Knowledge is Power! Literally! Cool 
Knowledge is Power; Absolute Knowledge is Absolutely Shocking!
Dollar Shave Club. Best Razor I've ever used
Certified 18650 Cell Reclamation Technician
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#6
thanks to both of you and your help, i went with 24V cause that inverter / charger hardware will be moving to a portable system in a Large Pelican case later fro a family member. :Smilehere is method to my madness...
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#7
Then I understand and approve your approach Big Grin
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 83kWh LiFePo4 | 10kWh 14s 18650 |  66*260W Poly
Upcoming: 14S 18650~30kWh | Automatic trip breakers, and alot more
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