Battery SOC minimum %

wingnut771 said:
Let me understand this properly, are you complaining about 10 000 cycles is not enough to get to 70% SOH?
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No just pointing out that this notion that after x time we will still have a battery that is 80% and can use this for a nother 20 years just at lower capacity is just a marketing gimmic



Thag hoes against the manufacturer guidelines



Now yes i use stuff outside guidelines but many won't the moment they become aware of it
 
leon.davibe said:
No just pointing out that this notion that after x time we will still have a battery that is 80% and can use this for a nother 20 years just at lower capacity is just a marketing gimmic



Thag hoes against the manufacturer guidelines



Now yes i use stuff outside guidelines but many won't the moment they become aware of it
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Lets table this for 20 years.
 
cavedog said:
So what damage do you need to do to a battery with a bms to get like 40% SOH? I though BMS protects the batteries from damage?

As it stands my Ecco battery bms is reporting 8 cycles which seems correct from when my system went live so that is 1 a day. At the 6000 rated cycles that is 16 years at least. Thats crazy. I guess if I finally switch to SBU mainly trying to be off grid the cycles will increase especially in bad weather where it might cycle a few times a day.
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Imo a bms is a crappy device that only prevents fires

Especially passive balance ones which most are

Lots of drift can happen in certain scenarios of and then Can never be solved by the bms

And you only become aware of this if the battery hits 0%

never hitting 0%soc helps hide this fact
 
leon.davibe said:
Imo a bms is a crappy device that only prevents fires

Especially passive balance ones which most are

Lots of drift can happen in certain scenarios of and then Can never be solved by the bms

And you only become aware of this if the battery hits 0%

never hitting 0%soc helps hide this fact
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tl/dr version: do what you want, LFP doesn't care.
 
leon.davibe said:
Yea this can fix
Most crappy batteries

The balance cables of the pace bms matched it so i did not even have to replace those

Just 3d prjnted a housing for the coms and screen as the coms board holes did not match
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I still have no clue what you talking about.
 
DTBA said:
Pacebms can balance per cell but only does at charging. It has a cutoff voltage per cell by default at 3.65 volt it will cut the charge mosfets so over charge won't happen
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Only balances while chargjng on my shoto

So essentially balances for 5-10 minutes per cycle

How stipud is that

6 months of trying to nurse it with all kinds of behaviour to get it to balance i just gave up
 
Last edited:
wingnut771 said:
I still have no clue what you talking about.
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Replaced a bms on a broken battery
Bms failure

The jks bms plugs matched the existing pace type bms so just used the existing cables in the battery

Instead of fitting the cables supplied with jkbms
 
leon.davibe said:
Only balances whole chargjng on my shoto

So essentially balances for 5-10mjnutes per cycle

How stipud is that

6 months of tryjng to nurse it with all kinds of behaviour tkbget it yo balance i just gave up
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Might need beach power supply and just give the cells a topup to 3.6v
 
wingnut771 said:
tl/dr version: do what you want, LFP doesn't care.
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Safety wise yea

Degradation wise not so much

A user can abuse a battery in the safe parrameters

Especially if stupid enough to fall for the 20-80 bullshit

Yes that works with a lithium with a non g
glat voltage curve

With lifep04 not so much

Yes you can try 20-80 usage on average

But you have to hit 100 regular to know that you are actually in 20-80

And not 0-60
So yea if you use 40-80 and it drifts to 20-60 you recalibrate at full charge lets say every 3-7 days sure

If not you are just probably breaking your own battery
 
DTBA said:
Might need beach power supply and just give the cells a topup to 3.6v
Click to expand...
Eventually i just did opened up the battery and manually balanced it

Edit have one problem cell so just routed cable out side

So if it gets out of wack when pack is full i just top up this one cell
 
leon.davibe said:
Safety wise yea

Degradation wise not so much

A user can abuse a battery in the safe parrameters

Especially if stupid enough to fall for the 20-80 bullshit

Yes that works with a lithium with a non g
glat voltage curve

With lifep04 not so much

Yes you can try 20-80 usage on average

But you have to hit 100 regular to know that you are actually in 20-80

And not 0-60
So yea if you use 40-80 and it drifts to 20-60 you recalibrate at full charge lets say every 3-7 days sure

If not you are just probably breaking your own battery
Click to expand...
Lets table this for 20 years.
 
leon.davibe said:
Eventually i just did opened up the battery and manually balanced it

Edit have one problem cell so just routed cable out side

So if it gets out of wack when pack is full i just top up this one cell
Click to expand...
You are a fringe case with a faulty cell.

Nobody cares. DIY FTW!
 
I set my bms to shutdown at 0%

And then manage the bank via solar assitant time based automations to run down to 30ish

May run lower if i get more solar capacity up

This is what i need to have a full boob at the momemt
 
leon.davibe said:
I set my bms to shutdown at 0%

And then manage the bank via solar assitant time based automations to run down to 30ish

May run lower if i get more solar capacity up

This is what i need to have a full boob at the momemt
Click to expand...
You're lucky you have a bms that allows you to go to 0%.
 
wingnut771 said:
Thanks for correcting me and showing pylon are a bunch of pussies where they only take their cell voltages to: 3.56V.

Correction: please show cell voltages at 53.5V?
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It is actually a good practive
By the time you hit that voltage the battery is full anyway

Cell manufacturers actually suggest that the charge amps has to taper off when ad uoj get to the top

Which most bms's can't do

Lowering the charge voltage accomplishes this

Shoto does the same thing
Or it does on my 15s shoto anyway
Limits pack voltage to 54v

But then they allow cells to pop way above 3.65v and well below 2.5v

So yea most of these batteries
That uses these pace type bms's is just cheap chinese crap imo

Marketed as premium brands

Imo they are all just ****

Sure well known brands may spend more effort in cell selection and pre balance

But hardware wise they are all ****

Just a fire prevention device nothing more
 
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