LIFEPO4 Battery discussion thread

[DTBA]

Took a chance on this https://www.bobshop.co.za/sunnew-sn...fepo4-wall-mount-inverter-battery/p/636132856
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Was hoping for a pacebms but no luck.

Soo its reading .10v higher on the battery bank then any of the other bank. Also its pulling the lowest amps charging and discharging .

I Don't have multimeter good enough or DC amp meter to say if the bms is out.

It has the longest cables in the bank but when charging it always have higher voltage same discharging,

Also amps is lowest while charging and discharging.

I would have said its the small silicone cable inside but even at idle the BMS is showing 0.10v more then the full bank.

Might be a good idea to replace the BMS with a JK and the cables inside as well.





If I had multimeter good enough then I could double check it.


Some day if I have installed more batteries ill take this one out.



For now stay away from it.

 

[wingnut771]

Soo its reading .10v higher on the battery bank then any of the other bank. Also its pulling the lowest amps charging and discharging .

I Don't have multimeter good enough or DC amp meter to say if the bms is out.

It has the longest cables in the bank but when charging it always have higher voltage same discharging,

Also amps is lowest while charging and discharging.

I would have said its the small silicone cable inside but even at idle the BMS is showing 0.10v more then the full bank.

Might be a good idea to replace the BMS with a JK and the cables inside as well.





If I had multimeter good enough then I could double check it.


Some day if I have installed more batteries ill take this one out.



For now stay away from it.

I guess you never get 2 battery's with identical internal resistance. I'm not concerned about this, they should all even out in the end. Also, crimps and lugs make a huge difference as shown in Will's latest videos.

 

[DTBA]

I guess you never get 2 battery's with identical internal resistance. I'm not concerned about this, they should all even out in the end. Also, crimps and lugs make a huge difference as shown in Will's latest videos.

I do agree

 

[wingnut771]

 

[duderoo]

Anyone set the TOU percentages for a Deye inverter via the app or web portal?

 

[cavedog]

So you just can't have a normal conversation with someone about lifepo4. Yesterday I had an argument with someone when he asked how far I discharge and I said well 2 to 3% sometimes on the SOC counter of the battery and he was like no dude you are damaging the batteries. They should never discharge lower than 25%....

 

[wingnut771]

So you just can't have a normal conversation with someone about lifepo4. Yesterday I had an argument with someone when he asked how far I discharge and I said well 2 to 3% sometimes on the SOC counter of the battery and he was like no dude you are damaging the batteries. They should never discharge lower than 25%....

 

[denmendez65]

So you just can't have a normal conversation with someone about lifepo4. Yesterday I had an argument with someone when he asked how far I discharge and I said well 2 to 3% sometimes on the SOC counter of the battery and he was like no dude you are damaging the batteries. They should never discharge lower than 25%....

Like my "5%" at 51V is going to damage anything

 

[cavedog]

Like my "5%" at 51V is going to damage anything

A lot of people also take the SOC counter a gospel. Like all my batteries cut off when lowest cell is 2.7v. AI reckons that is roughly 3% capacity left on that cell so if I have my cutoff set to 5% that means technically it's 8% give or take.

I have cheapish batteries that I want to max my ROI on right now because in 10 years the batteries will probably be half the price.

Solar technology is moving so fast that it's prematurely aging the tech so these 15 - 20years talk is crazy.

 

[ghaye]

A lot of people also take the SOC counter a gospel. Like all my batteries cut off when lowest cell is 2.7v. AI reckons that is roughly 3% capacity left on that cell so if I have my cutoff set to 5% that means technically it's 8% give or take.

I have cheapish batteries that I want to max my ROI on right now because in 10 years the batteries will probably be half the price.

Solar technology is moving so fast that it's prematurely aging the tech so these 15 - 20years talk is crazy.

In ten years battery technology would have moved on by leaps and bounds.

 

[cavedog]

AI calculations on my 5.12kW Ecco battery.

268 cycles to date. 8 months old. 1.372MWh moved through it at an average of 1.09 cycles per day. Remaining life at this same rate is roughly 14.4 years left and then it's roughly at 80% capacity left after that.

Crazy so when people say don't discharge the batteries too much I feel like I want to turn around and walk away when they are still speaking.

 

[DTBA]

Already seen that you will loose more with calendar aging then cycling them so run them and run them hard

 

[ghaye]

I don't have access to the details on my battery but Victron does have some reports and for July this is what I found...


And this is for January...


This is for 6 months (Jan till end June)


So extrapolating that lot it seems my total after 6 years is somewhere around 1600 cycles.