Dear Community,

I would like to have your opinion...

I currently run an 48v off-grid system on a boat with:

16 x TrinaSolar panels 275w

2 x Voltronic inverters MKS 5kva (parallel)

12 x Newmax Gel batteries 150ah

My batteries might reach end of life soon and I'm considering to replace them with LiFePo4.

I live in Egypt and I couldn't find any proper LiFePo4 packs here locally. That's why I might order directly from China.

There is lots of Chinese companies offering all kinds of LiFePo4 battery packs.

I contacted a few and already got some interesting offers, but I'm not sure about quality issues and if I shall take the risk.

They all sound quite promissing and the prices are not bad.  For example:

48v100ah from EV Lithium for 1500$

http://www.evlithium.com/LiFePO4-Battery/606.html

48v100ah from Meritsun for 1380$

https://www.meritsunpower.com/telecom-solar-energy-storage-lithium-battery-system

Or 48v300ah from Yiyen for 5000$

https://www.yiyen.com/product/battery-energy-storage-system-ess

Anyone of you has experience with LiFePo4's of that kind from China?

I'm pretty sure they could work well with my Voltronic inverters. But I'm wondering if they deliver what they promise...

I know that many users of this forum swear by PylonTech or BlueNova. No doubts, they must be great. But quite expensive and also not easy to get to Egypt.

Any advice is highly appreciated

Felix

 

And I just got the datasheet and specs for the YIY ESS...

3 x 48V(51,2v)100ah parallel = approx. 15kwh for 5000$ + shipping around 500$ + custom clearance...

Sounds not bad.

Would love to have your opinion.

Thanks

 

Battery pack 5.2KWH YIY.pdf

All the big battery makers use cells made in China (Winston, CALB, Sinopoly), so usually the difference lies in the BMS. The pictures look good, but that is as much as I can tell you 🙂

No other feedbacks or opinions?

Comparing datasheets and specs I tend to go for the YIY ESS.

3 x 5.2Kwh for 5000 USD

Sounds like a quality product.

Should perfectly work with my existing 16 x TrinaSolar Panels 275w and 2 x Voltronic Inverters MKS 5KVA

Would highly appreciate more opinions!

Thanks a lot

YIY - 5.2KWH.pdf

Hi, Felix. It seems you have installed the Yiyen batteries. I am also thinking of installing Yiyen 24V 300Ah battery pack. Can you please provide feedback/review with regards to safety, reliability and any issues about the battery? Thanks.

4 hours ago, Mazs said:

Hi, Felix. It seems you have installed the Yiyen batteries. I am also thinking of installing Yiyen 24V 300Ah battery pack. Can you please provide feedback/review with regards to safety, reliability and any issues about the battery? Thanks.

Hi Mazs,

Yes, I ordered 2 packs 48V 150Ah in March directly from Yiyen, China.  Excellent support with shipping,.paperwork and stuff. 3 weeks later I received them and installed them straight away. Since then they have been working perfectly, without any issue. The internal BMS seems to do a good job. Just... the BMS monitoring software only works on windows. And you have to order the CANUSB Adapter seperatly to monitor the batteries. So, I connected the two batteries via CANUSB to a Intel Computer Stick with Windows, and so I can monitor the batteries via VNC from anywhere.

After sales support, i.e. technical questions, monitoring, etc. is very good.

Till now I have 50 cycles on the batteries and they work perfectly. I am happy!

Cheers,

Felix

This is great. I have a few questions. Did you need any special settings in your inverter? What is your absorption voltage set as and for how many hours? What is the low voltage cutoff level? How does your inverter know when the battery is fully charged? Via a BMV?

It may be a great idea to document your setting up of the inverter, battery and your charging practices  to help others in future.

Thanks.

Edited July 4, 20197 yr by Mazs

Hey,

I think I just answered a few of you questions in the other reply.

No special inverter settings needed. Just...

Bulk charge voltage: 56V

Float: 55V

Cut-off: 48V

LiFePo4 don't need absorption. Just set bulk and float voltage. BMS cares about the rest.

I do have a BMV-702 installed. It's connected to the batteries and ICC. Like this I have all important info in ICC, like SOC, Ah consumed, time left, etc.

If I want to check more details about my battery packs, I have to lock at the BMS.

Attached 3 screenshots:

1. ICC Dashboard

2. YiY BMS Overview

3. YIY BMS Details

Hope this helps...

Cheers,

Felix

Very informative.

Wondering how the inverter-charger knows that the battery is full since your battery BMS is not connected to your inverter.

I assume the BMS shuts down the battery if the voltage drops to the Cutoff level.

Thanks a million.

Edited July 5, 20197 yr by Mazs

Thanks Felix and Mass for this thread. I am off-grid in British Columbia Canada, also considering a YIYEN battery pack for the same reasons (mainly cost, but you also have to admit they're good looking!).

Nice to have some user details and feedback.

we tried the sinopoly batteries, bought on amazon.com.

6 months till now, working great !

https://www.amazon.com/dp/B07SCZ7PBF/ref=twister_B07NKGSR7H?_encoding=UTF8&psc=1

 

 

 

I know this is an old thread, but I did go ahead and buy a 20.5Kwh battery from YIYEN before xmas and it finally arrived. I'm very pleased with my purchase so far: YIYEN was great at communication, they followed-up nicely, the battery arrived VERY WELL crated/packaged and it looks rock-solid and like a very good quality product.

I wish I had known more about what was involved with sea freight coming into Canada and all the fees, charges, duties, taxes, dock fees, wharehouse fees, etc. etc. Definitely not as simple as ordering from Amazon lol. but all is good now... Some pics attached.

 

Damn, that is a neat setup. I like the idea of all four batteries connected to the Busbars at the bottom, and the fact that all the connections are at the back of the unit....