Bloemfontein upcoming install

[Sc00bs]

On 2021/11/12 at 10:27 AM, Tariq said:

the 5 kW is rated at 6500 watts total, so 3250 watts per mppt is recommended, @Sc00bs, we waiting for your input, as you have over 12 k w on his 8 kw Sunsynk.

So @Tariq, my reason for putting the extra panels was not for the days when there is loads of sun but rather that I still don't have to worry about power when it is overcast and easily make my requirement. My daily consumption is usually around 50kw/hr which I cover pretty easily even on overcast days.

I have actually set the max charge rate on my batteries down to 100A (+-5kw), they allow for up to 160A to hopefully increase their life expectancy. My max power produced has been 11.9kw at which point it would have been putting 4kw into the batteries if the load was 8kw. Max on one of my strings is 6.78kw on my West facing string

My batteries are all charged by 11:00 when the sun is out.  

Max amperage on my Inverter over the last 7 days is 19.9A which is I think the max my JA Solar panels produce.

I have 455W JA Solar panels which max out at 9.93A Max Power Current

[Nexuss]

Hey @Sc00bs what is your string voltages at roughly?  I also have the 455 JA panels and see them at over 11 amps regularly. 11,6 Amps in todays log. 

[Nexuss]

18 hours ago, Leshen said:

I think what you guys fail to understand about the Hubble AM2 is that the cells are rated at 2.5C. Thats 250A at 50V. So do you really think that 100A will be a heating issue for this battery? 

The safety concern is not for when the battery is working like it should ,when something goes wrong these cells are prone to thermal runaway, and that is a fact.  At that point you have to rely on the Hubble's internal fire suppression system to save your house from burning down.

[P1000]

19 minutes ago, Nexuss said:

The safety concern is not for when the battery is working like it should ,when something goes wrong these cells are prone to thermal runaway, and that is a fact.  At that point you have to rely on the Hubble's internal fire suppression system to save your house from burning down.

I'm pretty sure the battery management will do something before the cells reach 170℃ (there are at least 4 temperature sensors in contact with the cells). Not that NMC is my favourite battery chemistry, but I don't think you should be concerned about that. The longevity argument is a much stronger one.

One thing that does baffle me is that NMC is supposed to be more expensive than LFP for the same capacity - but the Hubbles aren't.

[Leshen]

2 hours ago, Nexuss said:

The safety concern is not for when the battery is working like it should ,when something goes wrong these cells are prone to thermal runaway, and that is a fact.  At that point you have to rely on the Hubble's internal fire suppression system to save your house from burning down.

I'll make sure to include a fire extinguisher with each install going forward. 

Thanks for the heads up. 

[Leshen]

5 hours ago, 87 Dream said:

Ditto 100% agree with this comment. We need a safety culture. This device is in our homes. At most we best share education on the risks. 

 

Don't think this will be a quick fix. But at least awareness is now out there. 

I really do not want to trash any product or scare anyone here on the NMC battery. But at the very least you need to be aware of the dangers should anything go wrong. You should also feel free to question the safety measures on the subject. 

What I as an installer/ manufacturer/ client/ end user, needs to know is where to best place this device & what is the best way to know if anything went wrong, what to do. 

My attention of the subject came from my work in aviation. There is also a reason it is forbidden to be carried on passenger aircraft & carriage only allowed in very small quantities & in a very controlled way but only on Cargo Aircraft.

I have all the respect for any local manufacturer trying to make it in this game, however, answers on the areas of concern need to be addressed. Ignoring the questions as a buyer or as a manufacturer only leads to actually asking did they actually test these units in a runaway scenario under controlled conditions? What is the fire suppression strategy? How does it work? I can tell you that we do not even attempt to fight these fires, the temps are so high & gassing can be toxic. So maybe a fire extinguisher might not be useful maybe a smoke hood to be safe might be added. In a small non ventilated area is this a good idea? This is not a gas cylinder sitting outside ones home in a cage that has less risk. This is inside most homes & in high concentrations. 

We talk about temperature rises of 25°C per second & can reach temps in the range of 600°C - 900°C.

This is about education and safety full stop.

This unit is widely sold so if I owned one or was considering buying one it's good to know this information on the risks & threats and how to mitigate them. Let's be well prepared & informed. This goes for LFP also, but this is much less risky or prone to thermal runaway, but still the risk exists.

87

 

 

 

 

Do you think that cell phones and laptops use LFP or NMC cells?

[Yellow Measure]

Thermal runaway of LFP = 270 degrees C

Thermal runaway of NMC = 210 degrees C

https://batteryuniversity.com/article/bu-205-types-of-lithium-ion

So yes, LFP's thermal runaway is higher. But please, let's quit the unnecessary fearmongering. If some in this thread were to be believed, we would have headline news of batteries exploding all over the place (and only the NMC ones mind you)

We need to be pragmatic: All contemporary storage has risk, and risk is acceptable to the many who own them. The difference between the two chemistries' thermal runaway is 60 degrees C. Who runs their batteries at 200 degrees C and higher? If one is hitting those temperatures then it can only mean a faulty BMS or internal wiring / contact issues, and if that is the case, 60 degrees means absolutely nothing, the temperatures of an arc reaches almost 20,000 degrees C, 60 degrees is not going to save you    

I will light a candle for the fearmongers, if they truly believe their own fears, they will need it, because they will be sitting in the dark.

Edited November 17, 2021 by YellowTapemeasure

[Leshen]

3 minutes ago, YellowTapemeasure said:

Thermal runaway of LFP = 270 degrees C

Thermal runaway of NMC = 210 degrees C

https://batteryuniversity.com/article/bu-205-types-of-lithium-ion

So yes, LFP's thermal runaway is higher. But please, let's quit the unnecessary fearmongering. If some in this thread were to be believed, we would have headline news of batteries exploding all over the place (and only the NMC ones mind you)

We need to be pragmatic: All contemporary storage has risk, and risk is acceptable to the many who own them. The difference between the two chemistries' thermal runaway is 60 degrees C. Who runs their batteries at 200 degrees C and higher? If one is hitting those temperatures then it can only mean a faulty BMS or internal wiring / contact issues, and if that is the case, 60 degrees means absolutely nothing, the temperatures of an arc reaches almost 20,000 degrees C.    

I will light a candle for the fearmongers, if they truly believe their own fears, they will need it, because they will be sitting in the dark.

Soon they will convince everyone to sleep with PBEs due to the thermal runaway and gassing caused by the NMC battery in their cell phones. 

Flat earth society...

[Sc00bs]

14 hours ago, Nexuss said:

Hey @Sc00bs what is your string voltages at roughly?  I also have the 455 JA panels and see them at over 11 amps regularly. 11,6 Amps in todays log. 

Max voltage on my 8s2p string over the last 90 days was 390v (usually sits at around 360v)

Max voltage on my 6s2p string 291v 

[JoeSlow]

Just came by to say hello again.

Seems the thread needs to be moved to the battery discussion board. 

So what has arrived:

1. DB Enclosures

2. All CB's

3. AC wires

4. Fuses and holders

5. 125 x 75 galvanised trunking used between my solar room and house.

6. Geyserwise package

7. Sunsynk 5 inverter

8. PV Panel clips

9. Surge arrestors etc

 

Waiting on:

1. 9 x Solar panels

2. Mounting rails

3. Bits and bobs

4. 2 x Very dangerous(apparently ) Hubble A2 5.5s

5. Earth spikes

6. 6mm PV wires

7. CloudLink

Edited November 17, 2021 by JoeSlow
Cloudlink added

[Yellow Measure]

16 minutes ago, JoeSlow said:

Just came by to say hello again.

Seems the thread needs to be moved to the battery discussion board. 

So what has arrived:

1. DB Enclosures

2. All CB's

3. AC wires

4. Fuses and holders

5. 125 x 75 galvanised trunking used between my solar room and house.

6. Geyserwise package

7. Sunsynk 5 inverter

8. PV Panel clips

9. Surge arrestors etc

 

Waiting on:

1. 9 x Solar panels

2. Mounting rails

3. Bits and bobs

4. 2 x Very dangerous(apparently ) Hubble A2 5.5s

5. Earth spikes

6. 6mm PV wires

7. CloudLink

Thank you for getting us back on track. When is your install scheduled for?

[JoeSlow]

6 minutes ago, YellowTapemeasure said:

Thank you for getting us back on track. When is your install scheduled for?

Will schedule once everything has arrived. Hopefully all will be here by Friday then we'll see.

[JoeSlow]

1 minute ago, 87 Dream said:

More than happy to concede on the subject, no point continuing into the abyss. 

Good luck with the install, apologies to the author of this topic

87

Well at least for my first post here I got to page 3! 

[Gerrie]

13 hours ago, 87 Dream said:

We all have a point of view.

A solution to this problem might be to put a notice label on each battery, CAUTION “Keep sharp objects, dart boards and nail guns at least 3meters away from battery to avoid runaway temperature”

 

[Gerrie]

Information is king and digging a bit into lab test and reports can expose some of the pros and cons to help make informed decisions. If a product have the potential to become a liability whether it’s safety or even just disposal of its always good to know.

[Nexuss]

7 hours ago, Gerrie said:

A solution to this problem might be to put a notice label on each battery, CAUTION “Keep sharp objects, dart boards and nail guns at least 3meters away from battery to avoid runaway temperature”

 

Since there is a cell phone battery argument being made here lets look at the difference between when a small cell fails vs large battery like the AM2.  

 

[Leshen]

42 minutes ago, Nexuss said:

Since there is a cell phone battery argument being made here lets look at the difference between when a small cell fails vs large battery like the AM2.  

 

How about you stop derailing this thread.

[Moderator2]

Forumites, let's show some respect to OP and keep the thread OT.

[JoeSlow]

Update:

Got the following over the weekend:

2 x 3m lengths of 75x100 PVC trunking

10 x 3m lengths of 25mm pvc trunking to go inside the 76 x 126mm galvanised trunking from solar room to house

This morning:

Batteries arrived.

Hopefully still today the last bit including the 9 x PV panels will arrive.