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isetech
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Anyone using Sunsynk batteries with a Sunsynk inverter? 

I should be getting my first Sunsynk inverter to play with soon. 

The question I have is related to the inverter capacity. I am trying to wrap my head around the battery capacity suitable for the inverter battery capabilities.

For example, the Axpert inverters I have installed in the past has a recommended 200 amp/hr capacity for a 5 KVA inverter. I have only installed backup systems with lead acid/gel and AGM batteries. 

If I install a 5 KVA Sunsynk inverter (Max. Charging Current (A) 120A Max. Discharging Current (A)  120A ) would this mean that I need at least 2 X 5 kwh - C0.5 rated lithium batteries or at least 1 X C1 rated 5.5 Kwh lithium battery (even this is a little low with a 100 amp charge and discharge) 

Buying 1 X 5.12 Kwh Sunsynk battery would restrict the inverter capability. I would need 2 or maybe even 3 Sunsynk batteries to get the full inverter capacity. Which could explain why nobody is using the Sunsynk batteries ? 

 

 

Cell Type - Lithium Ferro Phosphate (LifePO4 or LFP)

Nominal Operating Voltage - 51.2V

Nominal Capacity - 100Ah / 5.12kWh

  • Depth of Discharge (DoD) - 100%

  • Usable Capacity - 5.12kWh

  • Packing - 1P16S

  • IP Rating - IP40

  • Minimum Operating Voltage - 44.8V

  • Maximum Operating Voltage - 57.6V

  • Standard Charging Current - 50A

  • Max. Continuous Charging Current - 50A

  • Standard Discharging Current - 50A

  • Max. Continuous Discharging Current - 100A (1C, 25°C ± 2°C)

  • Max. Pulse Discharging Current - 200A (2C, 30S, 25°C ± 2°C SOC≥40%)

  • Standard Charging Method - 0.5C CC to 57.6V, CV at 57.6V till current is 0.05C

 

 
  • Min. Operating Temperature (no derating) - Charging: 0°C / Discharging: -20°C

  • Max. Operating Temperature (no derating) - Charging: 50°C / Discharging: 55°C

  • Operating ROH - 20% ~ 80%

  • Storage Temperature - -20 ~ 50°C

  • Self-discharging rate - ≤5% (25°C 50% SoC)

  • SoC @ end of product line - 40%

  • Insulation Resistance - >100MΩ

  • Voltage Difference in each module - ≤20mV

  • Inner Resistance of single Cell - 0.34 ± 0.05mΩ (fresh cell 30 ~ 40% SoC)

  • Altitude Below - 2000m

  • Weight - 48kg

  • Dimensions - 440 x 530 x 132mm (not include connector, MSD and other parts)

  • Expected Life @ 25°C - Greater than 10 years if used as per warranty.

 

 

 

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I see them advertised for around R30K (C rating 0.5) compared to Hubble for around R25K (C rating 1) The only difference, I havent seen any bad reviews on the Sunsynk, compared to the Hubble, that could be due to the volume of Hubble sales compared to the Sunsynk battery? 

 

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2 hours ago, isetech said:

Anyone using Sunsynk batteries with a Sunsynk inverter? 

I should be getting my first Sunsynk inverter to play with soon. 

The question I have is related to the inverter capacity. I am trying to wrap my head around the battery capacity suitable for the inverter battery capabilities.

For example, the Axpert inverters I have installed in the past has a recommended 200 amp/hr capacity for a 5 KVA inverter. I have only installed backup systems with lead acid/gel and AGM batteries. 

If I install a 5 KVA Sunsynk inverter (Max. Charging Current (A) 120A Max. Discharging Current (A)  120A ) would this mean that I need at least 2 X 5 kwh - C0.5 rated lithium batteries or at least 1 X C1 rated 5.5 Kwh lithium battery (even this is a little low with a 100 amp charge and discharge) 

Buying 1 X 5.12 Kwh Sunsynk battery would restrict the inverter capability. I would need 2 or maybe even 3 Sunsynk batteries to get the full inverter capacity. Which could explain why nobody is using the Sunsynk batteries ? 

 

 

Cell Type - Lithium Ferro Phosphate (LifePO4 or LFP)

Nominal Operating Voltage - 51.2V

Nominal Capacity - 100Ah / 5.12kWh

  • Depth of Discharge (DoD) - 100%

  • Usable Capacity - 5.12kWh

  • Packing - 1P16S

  • IP Rating - IP40

  • Minimum Operating Voltage - 44.8V

  • Maximum Operating Voltage - 57.6V

  • Standard Charging Current - 50A

  • Max. Continuous Charging Current - 50A

  • Standard Discharging Current - 50A

  • Max. Continuous Discharging Current - 100A (1C, 25°C ± 2°C)

  • Max. Pulse Discharging Current - 200A (2C, 30S, 25°C ± 2°C SOC≥40%)

  • Standard Charging Method - 0.5C CC to 57.6V, CV at 57.6V till current is 0.05C

 

 
  • Min. Operating Temperature (no derating) - Charging: 0°C / Discharging: -20°C

  • Max. Operating Temperature (no derating) - Charging: 50°C / Discharging: 55°C

  • Operating ROH - 20% ~ 80%

  • Storage Temperature - -20 ~ 50°C

  • Self-discharging rate - ≤5% (25°C 50% SoC)

  • SoC @ end of product line - 40%

  • Insulation Resistance - >100MΩ

  • Voltage Difference in each module - ≤20mV

  • Inner Resistance of single Cell - 0.34 ± 0.05mΩ (fresh cell 30 ~ 40% SoC)

  • Altitude Below - 2000m

  • Weight - 48kg

  • Dimensions - 440 x 530 x 132mm (not include connector, MSD and other parts)

  • Expected Life @ 25°C - Greater than 10 years if used as per warranty.

 

 

 

Rebranded Pylontech.

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Posted (edited)
6 minutes ago, isetech said:

Like most things in this country, you just smile :)

So the challenge is to find a C1 rated battery at a reasonable price, compatible with a Sunsynk inverter.

 

 

I love my Hubbles, and I also love my Pylontechs. If I did another install today, it would be Hubbles again.

 

Edited by YellowTapemeasure
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What does the following mean, does it not mean it is a 1C battery? 

  • Max. Continuous Discharging Current - 100A (1C, 25°C ± 2°C)

I am also heavily conflicted at the moment regarding battery choice. There seems to be no clear direction for a reliable battery, other than Pylontech. And in my case I cant really afford 3 batteries to overcome the 0.5 C rate.

 

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I'm not sure at what point did the recommended charge /discharge current of the pylontech batteries become their limitations.

I have US 2000c and 3000c Max Discharge current is 50A and 74A that is 1C is it not?

 

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18 minutes ago, Piper said:

I have US 2000c and 3000c Max Discharge current is 50A and 74A that is 1C is it not?

 

No its not 1C because its not continuous discharge at 1c its only for 5 mins odd . 

3 hours ago, Leonb said:

What does the following mean, does it not mean it is a 1C battery? 

  • Max. Continuous Discharging Current - 100A (1C, 25°C ± 2°C)

I am also heavily conflicted at the moment regarding battery choice. There seems to be no clear direction for a reliable battery, other than Pylontech. And in my case I cant really afford 3 batteries to overcome the 0.5 C rate.

 

That is 1C yes because it says continuous , the charging rate is 0.5C.

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11 minutes ago, Nexuss said:
32 minutes ago, Piper said:

I have US 2000c and 3000c Max Discharge current is 50A and 74A that is 1C is it not?

 

No its not 1C because its not continuous discharge at 1c its only for 5 mins odd . 

OK... I am lekker dof but keen to learn. If I have two 5kw, 48V, 0.5C pylontechs connected in parallel, is this not the same as having a single 1c, 1Kw battery.

I am confused about this whole "C" business. My current batteries are rated (by the manufacturer) at 200 a/h and I'm told (verbally, by manufacturer staff) that they are 1C. So what should I be able to pull from them consistently? (spec sheet says 100A).

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20 minutes ago, Bobster said:

OK... I am lekker dof but keen to learn. If I have two 5kw, 48V, 0.5C pylontechs connected in parallel, is this not the same as having a single 1c, 1Kw battery.

I am confused about this whole "C" business. My current batteries are rated (by the manufacturer) at 200 a/h and I'm told (verbally, by manufacturer staff) that they are 1C. So what should I be able to pull from them consistently? (spec sheet says 100A).

Yes, you will be able to match the power of the inverter with 2 x 5kWh 0.5C batteries. But that won’t make the batteries 1C. Each one is still 0.5C. The main issue, is in this case you have 2 x 5kWh batteries to match one inverter. You will spend more or less double on batteries. With 1C battery, you only need 1 x 5kWh battery to match 1 x 5kW inverter. 

Edited by PowerUser
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So its pretty simple , If you have a 100Ah battery and its rated for 100ah continuous discharge its 1C. If its rated at 50Ah continuous,its 0,5C. If its rated at 200Ah continuous its a 2C battery ect.

Your 2 0,5C 100Ah(200Ah total) batteries in parallel are the same as a 100 Ah 1C battery in terms of they both are rated at 100Amp continuous discharge ,but you have 2x the capacity with the 200Ah pack.

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11 minutes ago, Nexuss said:

So its pretty simple , If you have a 100Ah battery and its rated for 100A continuous discharge its 1C. If its rated at 50A continuous,its 0,5C. If its rated at 200A continuous its a 2C battery ect.

Your 2 0,5C 100Ah(200Ah total) batteries in parallel are the same as a 100 Ah 1C battery in terms of they both are rated at 100Amp continuous discharge ,but you have 2x the capacity with the 200Ah pack.

Fixed your units for you.

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As I scrap deeper into the battery selection and learn a little more by the day. 

If a Sunsynk inverter is capable of 120 amps (max charge and discharge rate) as per the spec sheet, it would mean a 5.8 KWH battery would be ideal or the closest I have found 6.1 KWH ? 

What else would be taken into consideration, the location temperature? Would high and low temperature variations change the capacity and life span of the battery considerably.


Does this apply to lithium batteries or only SLA batteries and if so, how would it affect the batteries. 

General SLA Batteries are usually rated at 20HR, meaning their current over a period of 20 hours. If a battery is rated at 20Ah capacity at 20HR, it means that the battery can discharge 1 Amp per hour over that 20 hour period. A High Rate Battery will typically be rated at 10HR or less.

 

 

 

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23 hours ago, Nexuss said:

So its pretty simple , If you have a 100Ah battery and its rated for 100ah continuous discharge its 1C. If its rated at 50Ah continuous,its 0,5C. If its rated at 200Ah continuous its a 2C battery ect.

Your 2 0,5C 100Ah(200Ah total) batteries in parallel are the same as a 100 Ah 1C battery in terms of they both are rated at 100Amp continuous discharge ,but you have 2x the capacity with the 200Ah pack.

OK.... my battery pack is rated 200Ah and 10kw/h, but I can only pull (per specifications) 100A continuously. So that's not 1C, right?

However the pack is comprised of two batteries that are wired in series (there is a cable from the positive terminal of one battery to the negative terminal of the other). So is it possible that the individual batteries are 1C, but the pack as a whole is not?

It seems to me that the only figure worthwhile is the simple formula you have provided, applied to the entire battery pack. By that measure, what I have is not 1C.

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 I am still trying to understand why a person would spend R20-25 K on a C0.5 rated battery ? Why would you spend R40k on 2 x C0.5 rated batteries to get same capacity of a C1 rated battery? 

It just seems crazy, maybe it has to do with the cycles or there must be something.

What am I missing ? 

 

 

 

Edited by isetech
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What I have heard through the grape vine, there is rumour that if a Sunsynk inverter and a battery are used together they would hold a 10 year warranty compared to a 5 year warranty currently offered ( just a rumour). 

The question would then be, would you prepared to pay almost twice the price to get 10 KWH of battery for double the warranty ? It doesnt make sense I would rather buy an additional battery 5 years later.

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32 minutes ago, Bobster said:

It seems to me that the only figure worthwhile is the simple formula you have provided, applied to the entire battery pack. By that measure, what I have is not 1C.

Correct . If you parallel 2 or more 0,5C batteries they are still 0,5C batteries . Only thing that changes is the amount of amps you can pull from the pack doubles.

34 minutes ago, isetech said:

 I am still trying to understand why a person would spend R20-25 K on a C0.5 rated battery ? Why would you spend R40k on 2 x C0.5 rated batteries to get same capacity of a C1 rated battery? 

You dont get the same capacity you get double the capacity 200Ah vs 100Ah. Only thing that is the same is that they can both be discharged at 100A continuous.

Secondly 0,5C rated batteries will last much longer than 1C batteries. You can see this in the warranty and cycles . Then when you are comparing the Hubble AM2 specifically which uses NMC chemistry which does not typically last as long as LFP batteries it becomes clear why 0,5C batteries are guaranteed to last much longer. Generally cells with higher volts dont last as long as cells with lower volts 4,2V for NMC vs 3,65V for LFP. 

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16 hours ago, isetech said:

 I am still trying to understand why a person would spend R20-25 K on a C0.5 rated battery ? Why would you spend R40k on 2 x C0.5 rated batteries to get same capacity of a C1 rated battery? 

It just seems crazy, maybe it has to do with the cycles or there must be something.

What am I missing ? 

 

 

 

Download and compare the PDF spec sheets for the batteries. If I recall, Hubble indicates only 3000 cycles to 90% discharge, and 6000 cycles if you discharge to 50% charge only. Or thereabouts. The Pylontech indicates 6000 cycles lifespan if you discharge all the way down to 90% or 100% or around there. It boils down to choosing a higher power delivery versus a greater cycling life, at least on paper. Speaking under correction, open to admonishment from anyone who knows better, but if you calculate the Levelised Cost of Storage per kWh cycled in and out over the life of the battery, then Pylontech shows lower cost per kWh. But you need twice as many batteries upfront for the same power output. Again, many disclaimers out there, but I put it to you to test my suspicion that Pylontech has economic strengths as an alternative if you plan for pulling the plug on Eskom altogether and cycling your entire demand daily or most evenings, while Hubble has cost advantages if you are looking for occasional short-term loadshedding backup or running mostly daytime directly off solar. But do your own maths for your scenario.

Edited by GreenFields
comma
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4 minutes ago, GreenFields said:

Download and compare the PDF spec sheets for the batteries. If I recall, Hubble indicates only 3000 cycles to 90% discharge, and 6000 cycles if you discharge to 50% charge only. Or thereabouts. The Pylontech indicates 6000 cycles lifespan if you discharge all the way down to 90% or 100% or around there. It boils down to choosing a higher power delivery versus a greater cycling life, at least on paper. Speaking under correction, open to admonishment from anyone who knows better, but if you calculate the Levelised Cost of Storage per kWh cycled in and out over the life of the battery, then Pylontech shows lower cost per kWh. But you need twice as many batteries upfront for the same power output. Again, many disclaimers out there, but I put it to you to test my suspicion that Pylontech has economic strengths as an alternative if you plan for pulling the plug on Eskom altogether and cycling your entire demand daily or most, evenings, while Hubble has cost advantages if you are looking for occasional short-term loadshedding backup or running mostly daytime directly off solar. But do your own maths for your scenario.

I am currently discharging a minimum of 7-8kwh from my 7kwh pack every day. The more you utilize the battery the faster its paying for itself.

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33 minutes ago, Nexuss said:
1 hour ago, Bobster said:

It seems to me that the only figure worthwhile is the simple formula you have provided, applied to the entire battery pack. By that measure, what I have is not 1C.

Correct . If you parallel 2 or more 0,5C batteries they are still 0,5C batteries . Only thing that changes is the amount of amps you can pull from the pack doubles.

My thinking was that 2 0.5c 5Kw/h batteries in parallel amounts to a single 1C 10kw/h. But now I think that's wrong. Because if you hook them up in parallel your capacity increases, but so does the current. So you now have 10Kwh = 200Ah, discharging at 100A. So still 0.5C, but you are getting 100A.

I found the spec sheet for my batteries that was attached to the original quote. The numbers are 51.2V and 200Ah. That gives 10,24 KW/h. The spec sheet says they can be discharged at 1C, but I think that's more than my inverter can handle (4.6kw or 20A AC on the backed up circuits). So in this case that 1C is no use because the inverter can never draw that much. 



 

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2 hours ago, isetech said:

 I am still trying to understand why a person would spend R20-25 K on a C0.5 rated battery ? Why would you spend R40k on 2 x C0.5 rated batteries to get same capacity of a C1 rated battery? 

It just seems crazy, maybe it has to do with the cycles or there must be something.

What am I missing ?

 

You are getting double the capacity. I assume you are referring to a typical 5kWh battery - so lets say Hubble vs Pylontech. The Pylontech is capable of delivering 2.4kW continuously (0.5C) and the Hubble 5.1kW (1C). The capacity is not affected by the C rating - you can do 2 hours at 2.4kW on the Pylon, but 1 hour at ~5kW for the Hubble. This is mostly down to the different battery tech - Pylon uses LiFePO₄, Hubble NMC. NMC is usually more expensive than LiFePO₄ so the Hubble battery should be more expensive only going on that. The different battery chemistries have different pros and cons - IMO NMC is not ideal for ESS in a home, but I will not force my opinion on anyone (and LG resu is a good proof of why I might be wrong). Personally why I would choose Pylontech over NMC is simply the long term tests. Sure you have to now buy double the capacity to service the same load, but you were going to do that anyway at a later stage, weren't you?

An alternateve reality is that you buy BSL or FreedomWon eTower, which is LiFePO₄ with 1C (although prices seem to have skyrocketed recently.)

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