Battery SOC minimum %

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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You should ask for a firmware update.

My oldest two batteries are now just over 5 years old with about 1450 cycles on each. When I initially purchased them the BMS only balanced while charging.

I asked for a firmware update (this is more than 4 years ago) which I got directly from PACE after the importer provided me with a contact person at PACE in China. Since then the BMS balances the cells irrespective of whether there is a charge current or not (as long as the cell delta exceeds what you set in the BMS setting it will balance).

The reason why PACE is so popular is because it is one of the most configurable BMSes around.
 
denmendez65 said:
Pace doesn’t have individual balancing I believe? So chances are there is a hard limit on the DOD. Maybe 95%? If you go to 100 you run the risk of your cells not being balanced.

Then you have to rely on the over voltage charging thing people talk about here.
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No hard limit on the DOD with PACE BMS. Here is my battery at 0% SOC, picture taken from PBMS Tools. This was when I did a capacity test a while back.

PACE does not actually have a upper and lower SOC limit in the BMS settings where it cuts off (it does have a warning for this, but no hard stop) . It uses pack and cell voltages exclusively for this.
 

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Koosvanwyk said:
You should ask for a firmware update.

My oldest two batteries are now just over 5 years old with about 1450 cycles on each. When I initially purchased them the BMS only balanced while charging.

I asked for a firmware update (this is more than 4 years ago) which I got directly from PACE after the importer provided me with a contact person at PACE in China. Since then the BMS balances the cells irrespective of whether there is a charge current or not (as long as the cell delta exceeds what you set in the BMS setting it will balance).

The reason why PACE is so popular is because it is one of the most configurable BMSes around.
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It should only balance above 3.45V. If it balances all the time then it is working against itself with LFP's flat curve.
 
wingnut771 said:
It should only balance above 3.45V. If it balances all the time then it is working against itself with LFP's flat curve.
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Indeed, you can set this voltage at which balancing should start. Mine is set at 3.45V
 

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I still need to actually plug in the cable and check the bms for proper settings I'm still working off voltage for SOC.
 
Koosvanwyk said:
You should ask for a firmware update.

My oldest two batteries are now just over 5 years old with about 1450 cycles on each. When I initially purchased them the BMS only balanced while charging.

I asked for a firmware update (this is more than 4 years ago) which I got directly from PACE after the importer provided me with a contact person at PACE in China. Since then the BMS balances the cells irrespective of whether there is a charge current or not (as long as the cell delta exceeds what you set in the BMS setting it will balance).

The reason why PACE is so popular is because it is one of the most configurable BMSes around.
Click to expand...
Might have to do that cause just balancing when charging is a issue of its a really unbalance battery. Had a takealot 5kw battery that was out of balance. Took ages but using lead acid mode I got it fixed.

Else it will charge trip OVP and report 100% soc and stops balancing.
 
Koosvanwyk said:
No hard limit on the DOD with PACE BMS. Here is my battery at 0% SOC, picture taken from PBMS Tools. This was when I did a capacity test a while back.

PACE does not actually have a upper and lower SOC limit in the BMS settings where it cuts off (it does have a warning for this, but no hard stop) . It uses pack and cell voltages exclusively for this.
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Its nice to have access to your BMS no matter what it is to see what its doing so you have an informed picture of what's what.
eg: you can see cell peaking at 3.65V when pack voltage is still at 54V because the bulk manufactorer factory never has time to match cells together at the same SOC (they should match cell capacities though and I'm sure they do, well maybe back in the day but now they are all the same I assume). The problem starts when one cell is 10% higher than the rest for some reason for example, the BMSs available on the market are not equipped to handle 300Ah cells with their puny mA passive setup. This is probably all the high voltage alarms new owners see when the battery is new and is not behaving normally but sorts itself out over time (weeks or months) without 90% of the users knowing any better.

I assume most of the batteries sold here has no access to BMS (like we see with bluetooth batteries on youtube), which I guess is a good thing, lots of damage can be done if a saboteur had access: eg; this one youtuber ordered 16 280Ah cells and was making a video how to top balance with a power supply before assembling with bms, somehow he bumped the knob on the power supply while reaching for something in the garage and bumped the voltage from 3.65V to 4.2V. The next morning all the prismatic eve 280k cells were swollen. Puffed up like balloons, brand new.

Long story short, he still built his battery (minus any compression obviously) and the pack could still handle 2C and had 80% SOH.

IMHO, anyone that can access the BMS should void the warranty, but who cares about a warranty when I have 16 cells on a shelf with all the terminals torqued to 5nm (triple checked, 1: assembly, 2: full load discharge test, 3: nope, that's it, I lied, only have to double check, well maybe check every 6 months).

Who needs a warranty anyway when a cell costs R2k and a BMS costs R2k.
 
wingnut771 said:
Its nice to have access to your BMS no matter what it is to see what its doing so you have an informed picture of what's what.
eg: you can see cell peaking at 3.65V when pack voltage is still at 54V because the bulk manufactorer factory never has time to match cells together at the same SOC (they should match cell capacities though and I'm sure they do, well maybe back in the day but now they are all the same I assume). The problem starts when one cell is 10% higher than the rest for some reason for example, the BMSs available on the market are not equipped to handle 300Ah cells with their puny mA passive setup. This is probably all the high voltage alarms new owners see when the battery is new and is not behaving normally but sorts itself out over time (weeks or months) without 90% of the users knowing any better.

I assume most of the batteries sold here has no access to BMS (like we see with bluetooth batteries on youtube), which I guess is a good thing, lots of damage can be done if a saboteur had access: eg; this one youtuber ordered 16 280Ah cells and was making a video how to top balance with a power supply before assembling with bms, somehow he bumped the knob on the power supply while reaching for something in the garage and bumped the voltage from 3.65V to 4.2V. The next morning all the prismatic eve 280k cells were swollen. Puffed up like balloons, brand new.

Long story short, he still built his battery (minus any compression obviously) and the pack could still handle 2C and had 80% SOH.

IMHO, anyone that can access the BMS should void the warranty, but who cares about a warranty when I have 16 cells on a shelf with all the terminals torqued to 5nm (triple checked, 1: assembly, 2: full load discharge test, 3: nope, that's it, I lied, only have to double check, well maybe check every 6 months).

Who needs a warranty anyway when a cell costs R2k and a BMS costs R2k.
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I see that the new pacebms has Bluetooth and wifi https://www.solarwaysuppliers.co.za/product/must-5-12kwh-48v-100ah-lithium-battery

pretty sure this is a pacebms
 

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cavedog said:
Ohh okay then my Ecco must also have a Pace BMS. It's exactly like the Must battery :D

Nice. Connected with the Paceex app via bluetooth.
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mind showing us the default parameter settings for ecco. I think they do lower full charge voltage to something like 56v
 
DTBA said:
mind showing us the default parameter settings for ecco. I think they do lower full charge voltage to something like 56v
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:)
 

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Yeah I was getting a bit happy about the Pace BMS reading peoples stuff here but nah. JK is still king. Pace has too many bugs. I guess that’s why it’s used in all these cheap lithium batteries out there.

 
denmendez65 said:
Yeah I was getting a bit happy about the Pace BMS reading peoples stuff here but nah. JK is still king. Pace has too many bugs. I guess that’s why it’s used in all these cheap lithium batteries out there.

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Seems with more than 1 battery just run it in Voltage mode. His review of Pace BMS new wifi/bluetooth version is horrible.
 
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