LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

[john61ct]

Besides reading this thread (long I know) another good one here: http://www.cruisersforum.com/forums/...-215514-4.html

Maine Sail is da man.

Also give Bruce @ Ocean Planet your close attention.

Also MS' summary notes here
https://marinehowto.com/lifepo4-batteries-on-boats/

**Everything** at that site is worth reading, very valuable. https://marinehowto.com/support, feel free to make a donation to help with those expenses.

He also has great articles in Practical Sailor, some with Nigel Calder, who's written The books, somewhat dated lead-based but excellent.

[john61ct]

Originally Posted by ruixulifepo4

I am Rachel from RUIXU battery.



All the Sinopoly 12V kits are made of Sinopoly brand new cells

Yes links please, to not only your own website, but shops on Ali, eBay, Amazon, whatever marketplace channels you use.

And, are you saying that all your packs comprise original cells actually manufactured by Sinopoly?

Can you also link to the datasheets or product pages for the BMS units you use?

[john61ct]

RuiXu store on Amazon, https://www.amazon.com/stores/node/17712984011

Their LFP cells plugged by YouTuber Will Prouse here
https://youtu.be/RAO5qARz6FA
https://www.youtube.com/user/errolprowse

note not much of a tech geek IMO, got his arse kicked in many threads in vandwelling forums last year.

newhaul credit posted here http://www.cruisersforum.com/forums/....php?p=2873633

______
exMaggieDrum at first thought they look like genuine Sinopoly, later questioned that since hers had the company name stamped into the prismatic cases.

______
My take:
Ali source for what looks the same, not that company though
https://antybattery.aliexpress.com/s...chText=lifepo4

Amazon merchant name matches this company
https://rxenergy.m.en.alibaba.com/fe...a277m.main.0.0

but the cells does not seem to actually be made by them.

_______
If these are Sinopoly, then unusually low (too good to be true) pricing from a third party seller IMO likely means sub-par QA rejects, or maybe even second-hand.

Which does not inherently mean poor value, but being well set up for stringent load testing soon after arrival would be critical, and shipping costs of rejected cells a major issue back to China.

I would really want to deal with a NA supplier for that reason.

_____

Originally Posted by newhaul

Well I just got the reply from ruixu battery.
The cost of the 200ah cells to build a 12 volt bank including all hardware and the BMS is $910 plus $270 shipping for a total of $1180.00. Includes the bms which is not included through Amazon.
And yes they said they said they accept PayPal but charge the PayPal fee to you.
So it is a bit cheaper than via Amazon but you also get the bms which separately costs $100 for the bms for the 100ah bank .

Don't know if this was actually the Amazon seller, the Ali store I linked to with the same name, maybe the same company, and maybe also this new member.

[weavis]

Nearly all Chinese vendors charge back the PAYPAL fee to the purchaser.

It actually stopped irritating me when I took a look at the money I lost on a computer program I sell. nearly 50 smackers a sale in bank charges! (PAYPAL is a bank)

Ce le vie.

[john61ct]

Just noticed that although this is Rachel's first post, she actually joined just a few days before newhaul posted that YT promotional video from Will.

Not drawing any definite conclusions from that myself, but FYI.

[CatNewBee]

Originally Posted by mike_kelly

I am used to using li-po and li-ion that are both unforgiving and can be damaged easily if not used and stored properly.



I am glad that LiFEPo4 are apparently less likely to burn your house or your boat down.


I am not familar with the term "prismatic" and don't find a definition on the net. I see they do not have balance leads available.

Hello Mike,

Prismatic cells are the big brothers of the cylindrical hobby cells. They have capaciies between 20Ah and 10000Ah, one of the big manufacturers is Winston Energy. They build cells for automotive, grid attached storages, submarines etc.

Cells available for DIY range from 60Ah...1000Ah.

The cells are bolted together by rigid bars, a LiFeYPO4 cell can yeld 3C current contimously, so you n3ed serious connectors.

Regarding BMS. You need one, definitely! No matter what you read here about shoulders and PSOC.

LFP cells and connectors have slightly different resistances, what leads to imbalances when cycling. There is no way to avoid that, there are no ideal pre-selested packs, they will drift.

There are various BMS designs for different applications. The cheapest are cell modules mounted on topp ov the cell poles, daisy-chained vor LVP / OVP, balancing currents are between 1A and 3A.

The next level are cell boards with a controller and Bluetooth like theb123BMS, they also measure the current and the cell temperature.

More advanced are packed BMS on an external unit, where only sensing wires need to be connected to the cell poles, They usually have also thermal cell sensors and connect to a shunt or a coil to measure the current.

You do not need high current balancers. 1..3 A are sufficient even for 1000Ah cells. The balancer have all the time t9 keep the cells in sync.

I use the REC ABMS on my 1000Ah house battery, it is an active BMS, means, it does discharge a single cell to charge the pack, less energy loss by heat, and it is in a IP67 housing, no cell modules, fully configurable, but not cheap. Look at the Internet for details, or read my thread.

If you have any specific questions, feel free to ask.

[ruixulifepo4]

Originally Posted by newhaul

links to your company website please

LiFePO4 Battery Solutions Factory | RUIXU

Or you can search RUIXU LiFePO4 battery from Alibaba or Aliexpress website.

Text me :518 223 9837 for more questions

[ruixulifepo4]

Originally Posted by john61ct

RuiXu store on Amazon, https://www.amazon.com/stores/node/17712984011

Their LFP cells plugged by YouTuber Will Prouse here
https://youtu.be/RAO5qARz6FA
https://www.youtube.com/user/errolprowse

note not much of a tech geek IMO, got his arse kicked in many threads in vandwelling forums last year.

newhaul credit posted here LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks - Page 420 - Cruisers & Sailing Forums

______
exMaggieDrum at first thought they look like genuine Sinopoly, later questioned that since hers had the company name stamped into the prismatic cases.

______
My take:
Ali source for what looks the same, not that company though
https://antybattery.aliexpress.com/s...chText=lifepo4

Amazon merchant name matches this company
https://rxenergy.m.en.alibaba.com/fe...a277m.main.0.0

but the cells does not seem to actually be made by them.

_______
If these are Sinopoly, then unusually low (too good to be true) pricing from a third party seller IMO likely means sub-par QA rejects, or maybe even second-hand.

Which does not inherently mean poor value, but being well set up for stringent load testing soon after arrival would be critical, and shipping costs of rejected cells a major issue back to China.

I would really want to deal with a NA supplier for that reason.

_____


Don't know if this was actually the Amazon seller, the Ali store I linked to with the same name, maybe the same company, and maybe also this new member.

I want to explain this:

1.All the Sinopoly cells we purchased from Sinopoly factory directly,all these are brand new cells,not second-hand battery,every cell would be tested before delivery.

We buy quantity in stock in our warehouse ,then retail on Amazon,Alibaba,Aliexpress,now we are opening the new store on Ebay.
Again,all the Sinopoly cells are 100% original brand new cells.I am not sure other supplier's,but ours are REALLY ORIGINAL SINOPOLY NEW CELL!!!

2.Another solution is our 12V drop-in series.now our main model for this series is 40Ah/10Ah/200Ah,all these models are BMS included(dorp-in series only can do in parallel,can't do in series),these are hot selling models in the market.this series are made by 100Ah brand cells (listed company "PENGHUI").100A BMS cost is about 90USD,this is the cost price. 150A BMS for 200Ah battery cost price is about 120USD.I will list our BMS info on Amazon soon,and I will send the link here.

3.Also,we can supply the LiFePO4 solution with metal case ,PVC wrapped on cusutomer's different size,voltage ,capacity requirement.

Below is All the link,hope my answer can help you,if any questions,you can tex me at any time,I am glad to answer at any time.

https://www.aliexpress.com/store/501...38285fb7pAteKc

https://rxenergy.en.alibaba.com/

https://www.amazon.com/LiFePO4-Phosp...t-items&sr=1-3

https://www.amazon.com/RUIXU-24V100A...F1MA063R2X5S76

www.ruixubattery.com/www.ruixulithiumbattery.com

Many thanks

[ruixulifepo4]

Will send you the link soon

[newhaul]

Originally Posted by john61ct

Just noticed that although this is Rachel's first post, she actually joined just a few days before newhaul posted that YT promotional video from Will.

Not drawing any definite conclusions from that myself, but FYI.

john not to not pick but I linked to the Amazon sales page not the video . Rachel is from the company I contacted direct and I told you that didn't I .

Buy a set of Lfp from somewhere or stop posting like you have a clue what's good bad or even ugly about running Lfp as a house bank.

[newhaul]

Originally Posted by ruixulifepo4

I am Rachel from RUIXU battery.

All the Sinopoly 12V kits are made of Sinopoly brand new cells
The 12V drop-in series are made by the brand cell in China. we have specification for the 12V series,if anyone need,pls message me.

Yes,we do not sell cells,we are LiFePO4 battery solutions factory in China.

Rachel we have already spoken on Alibaba b2b
My trucking company Newby hauling.

[JmanC]

Can you perform a capacity test with a lifepo4 bank ( specifically dropin) using nothing but a dc light bulb? Say a couple of high wattage together drawing about 0.3C total. Lfp has little voltage sag to the end, i read to about 10-15% soc. One lfp dropin I'm looking at states in their manual the lv disconnect is at 11.2v.
So running the lightbulbs until this cutoff how accurate would the calculated capacity be? Can you give a %?
Any compact devices that do this better? I dont have any fancy lab stuff and just want a good rough idea within 10% at least.
Cheers

[john61ct]

The key is maintaining the constant current all the way from 100% Full voltage down to 0%.

Rig something like a dimmer switch, watch your ammeter.

Stop at 11.99V for 0%, don't go lower, nor sit there, start recharging quickly.

The OTS load test devices handle that for you, e.g. BK-Precision top shelf, cheap but OK ZKEtech EBC/EBD series.

Better hobby chargers include that functionality too.

.3C of course will vary by cell capacity, a 200+Ah pack compared to a 3Ah one, very different.

[mike_kelly]

CatNewBee

"You do not need high current balancers. 1..3 A are sufficient even for 1000Ah cells. The balancer have all the time t9 keep the cells in sync."


I would think this depends on how fast you want the battery equalized.



So does anybody make a system with the balancers on the batteries networked to a charger that coordinates with the balancers? Otherwise you would have to control it manually since you can't have the battery charging with a balancer active.


Maybe LiFePo4 are very tolerant but I can't get my head around charging and then leaving a bunch of balancers turned on continuously to equalize. You are never going to get a full charge that way.



Anyone using Hall sensors instead of shunts?

[mike_kelly]

Originally Posted by john61ct

Yes


Dunno never heard of vacuum anything. Both protection and easy connections.

Lithium burns when exposed to air. All li-po chemistry are in vacuum sealed bags. IF they are over charged and produce gas, that is why they "puff". If the bags are punctured they catch on fire.