Water Drops Inside Lifepo4 Battery Case

[aussiecuunt]

Hey everyone,

Longtime reader, first time poster, I just registered today because I figured, I now need help of my own.

The batteries I am about to talk about are 12V Lifepo4 100AH.

I purchased some 2 Lifepo4 batteries, they have clear cases, so you can see inside them, I have only had them for a month but already having issues.
My biggest concern is there is water drops inside the case (water condensation building up on the inside).
This is a bit worrying because it can cause corrosion through the wiring, the BMS circuit and/or the internal terminals.



I have emailed the company and they said

The water drops in the case are normal for LiFePO4 batteries, there will be pressure release valve body on the side of the battery cells where is in the middle of the cells connecting bolts. There will be water vapour being released while you are charging and discharging. You are not the first person asked this, because there is no other clear cased Lithium batteries on the market so people don't know what happened in side the black battery.

Now this sounds extremely odd to me because

1. If the cells are needing to vent, that would me they are getting too hot, overcharged or something else.
2. The BMS should be preventing the cells from even getting too hot.
3. If Lifepo4 cells are known to vent and cause condensation inside the case, wouldn't the case have a vent to allow the condensation to escape?

Can someone please let me know if this is good/bad.


Issue #2 I am having is the batteries are supposed to have a low cut off protection of 9.2v (yeah I know, that seems too low huh?), yet the BMS is cutting the battery off at 12.2V-12.5V.

Issue #3 one of the batteries is not charging, when connected to my Victron 100/50, the battery will go from 12V to 13.5V in seconds. No current will flow into the battery at all, but the voltage will show full, despite not being full at all. Pretty sure my cabin would burn down if my battery when from 12V to 13.5V in 1 second. There is no way in hell my wires could handle 100Amps per second lol I have posted a video of this happening HERE <-- I posted it to YouTube.

The company claims this

I have watched your video, the LCD monitor displays the voltage you apply to it with your charger OR the battery voltage if you didn't connect the load. The SOC is calculated based on the voltage. Where it will shows 100% at 13.5v and 0% at 10.5v. I have attached the internal wiring of the LCD.

I can see when you connect the battery to the external power supply, the monitor shows 13.5v that's the voltage reading of your power supply. When you release the external power supply the reading dropped to 12v, this is the battery voltage.

Here is the photo they attached



However, the other battery doesn't do this, it chargers normally. In fact no battery does this!
The LCD display shows the voltage of the battery NOT the voltage applied to the battery from the Victron MPPT.
If when charging a battery, the charger showed the battery at full voltage, it wouldn't charge at all..so their reasoning makes no sense at all.
I know they're full of shit because the other batteries LCD display always and only displays the voltage of the battery NEVER the voltage applied.

Lastly, when connected in series, the batteries go out of balance pretty quickly (few minutes). Yes I have charged them fully individually.
one never stays at 13.5V. One of them will be at 13.5V while the other will be at 13.3V.


Oh also when even the smallest load (1Amp) is applied to the battery bank, the voltage will drop quite a bit, for example if they are at 13.3V, it'll drop to 13V.


Thanks heaps!

 

[aussiecuunt]

No one at all can help?
Did I post this in the wrong section?

 

[S Davis]

Can’t really comment on the battery performance not enough experience, depending on the humidity when they installed the cells and sealed the case there is a certain amount of moisture trapped inside. The batteries will get warm when charging and If you drop the outside of the case below dew point the moisture will condense on the inside of the case.

 

[upnorthandpersonal]

They LCD measures the voltage which is the highest, this means if the battery is 12v and you apply any voltage higher than 12, the lcd will read the higher voltage. Vice versa, if you apply a voltage lower than 12v, the LCD will read 12v which is the highest.

That's nonsense. If you have e.g. a LiFePO4 cell that is at 3.65V (full) and attaching a supply at 3.65V will read this 3.65V. However, take that same LiFePO4 cell at 3.3V and apply the same power supply (still at 3.65V) and the supply voltage will drop because it goes into constant current mode. It can not maintain the voltage and goes into constant current mode where it supplies as much current as it can until the battery voltage starts rising and it can get closer and closer to the 3.65V set. After that, the supply goes to constant voltage mode where both are now at 3.65V and current starts tapering off.

LifePO4 cells don't vent. If they vent, something is wrong. The electrolyte doesn't even have water.

 

[curiouscarbon]

the water drops, ideally, would not be forming inside the case

condensation of this degree is undesirable for reliability

may i ask what the ambient conditions are like temperature and humidity wise?

drying out the inside, sealing up the battery, and placing a packet of silica desiccant could mitigate this issue (of undesirable condensation)

like this



https://www.amazon.com/O2frepak-10Packs-Moisture-Absorber-Desiccant/dp/B08QTSJF7V/

the water will go into the packets, and they can be replaced for relatively low cost. should not be any harm to include a handful of packets in places that do not contact any electrical conductors. just another option. if the case is somewhat sealed then a few 100g packets ought to last a while (at least months?)

hope this helps somewhat.

 

[Gizmo740]

Voltage applied to a circuit will equalize based on current and potential. I have to believe your battery has more potential and will "drag" the voltage of the charge source down to battery level until current of charge source causes battery to saturate thus raising voltage of entire system. Controller settings determine current flow and bms is stop-loss protection for battery cells.

Unless the vendor did some creative wiring of the voltage display, it will always show the voltage of the system...not one source or another. It is possible I guess but based on reading responses from vendor I question their basic understanding of electronics...so doubtful.

Do you have access to bms settings? Have you checked charger settings?

Next would be to check connections assuming you can access case. If persists I would top balance individual cells (believe I see 4 in photo) as sounds like one or more triggers bms protection before others. This will cause issues both charging and discharging.

Condensation is possible but unlikely if you are keeping batteries at human friendly temperatures they like to be at. If application exposes batteries to lower or swings in temperature silica solution above will help. Highly doubt coming from cell vents and this would indicate bigger issues.

 

[Gizmo740]

Correct. Simply a display of system voltage. I'm betting loose connection somewhere and/or out of balance cells.

Issue 1: pack not sealed in vacuum so moisture present in air in case. Low ambient Temps and swings in Temps coupled with heat generated by bms and other electronics in case create condensation. SILICA packs solve this. Inspect cell vents and verify intact and dry. If not...I would retire or return pack.

Issue 2: bms cutting charge or discharge before expected pack values...assuming this is a newer pack. improper balance of cells at assembly or loss of balance over time. Rebalance cells.

Issue 3: covered

Lastly issue 4: related to issue 2. Adding faulty pack to good pack is not going to improve performance of system.

 

[A.Justice]

water drops inside the battery box are normal for LiFePO4 batteries. I have cut voltax battery open and the water was pooling inside. They LCD measures the voltage which is the highest, this means if the battery is 12v and you apply any voltage higher than 12, the lcd will read the higher voltage. Vice versa, if you apply a voltage lower than 12v, the LCD will read 12v which is the highest.

If you're the vendor of those batteries you need to specify that in your profile.

 

[RCinFLA]

The water drops in the case are normal for LiFePO4 batteries, there will be pressure release valve body on the side of the battery cells where is in the middle of the cells connecting bolts. There will be water vapour being released while you are charging and discharging. You are not the first person asked this, because there is no other clear cased Lithium batteries on the market so people don't know what happened in side the black battery.

Oh also when even the smallest load (1Amp) is applied to the battery bank, the voltage will drop quite a bit, for example if they are at 13.3V, it'll drop to 13V.
!

Whenever a container is sealed well, unless the air inside was flushed with dry gas like dry nitrogen, there will be water vapor trapped in the air. I do not expect it is usual for the inside of self contain 12v LFP battery case to be flushed with dry gas but if the battery was assembled in a humid environment there will be more captured moisture.

When environmental conditions lowers temp, air trapped inside may reach 100% relative humidity and condensate out.

The best way to prevent internal condensation is to have a small vent hole in the plastic case. You could drill a 0.1" small hole in the clear plastic case, at a location where you are not likely to hit a vital organ, and this will eliminate most internal condensation.

Problem with condensation is mixing with sodium salts also trapped on surfaces inside from human handling. Human hands have a lot of sodium on their surface which is also the reason you should not touch the aluminum battery terminal surfaces.

Salt mixed with water creates corrosion on most metal surfaces. Cleanliness during assembly is important and gloves should be used when handling to minimize salts from being deposited on surfaces.

Second, on voltage drop, this is normal. With very small cell load current there will be between 10 to 20 mV drop per cell in terminal voltage. This is why just paralleling cells will not fully balance their state of charge. For four cell 12v LFP, 40-80 mV drop.

 

[Steve_S]

Hey everyone,

Longtime reader, first time poster, I just registered today because I figured, I now need help of my own.

The batteries I am about to talk about are 12V Lifepo4 100AH.

I purchased some 2 Lifepo4 batteries, they have clear cases, so you can see inside them, I have only had them for a month but already having issues.
My biggest concern is there is water drops inside the case (water condensation building up on the inside).
This is a bit worrying because it can cause corrosion through the wiring, the BMS circuit and/or the internal terminals.

View attachment 74180

I have emailed the company and they said



Now this sounds extremely odd to me because

1. If the cells are needing to vent, that would me they are getting too hot, overcharged or something else.
2. The BMS should be preventing the cells from even getting too hot.
3. If Lifepo4 cells are known to vent and cause condensation inside the case, wouldn't the case have a vent to allow the condensation to escape?

Can someone please let me know if this is good/bad.


Issue #2 I am having is the batteries are supposed to have a low cut off protection of 9.2v (yeah I know, that seems too low huh?), yet the BMS is cutting the battery off at 12.2V-12.5V.

Issue #3 one of the batteries is not charging, when connected to my Victron 100/50, the battery will go from 12V to 13.5V in seconds. No current will flow into the battery at all, but the voltage will show full, despite not being full at all. Pretty sure my cabin would burn down if my battery when from 12V to 13.5V in 1 second. There is no way in hell my wires could handle 100Amps per second lol I have posted a video of this happening HERE <-- I posted it to YouTube.

The company claims this


Here is the photo they attached

View attachment 74181

However, the other battery doesn't do this, it chargers normally. In fact no battery does this!
The LCD display shows the voltage of the battery NOT the voltage applied to the battery from the Victron MPPT.
If when charging a battery, the charger showed the battery at full voltage, it wouldn't charge at all..so their reasoning makes no sense at all.
I know they're full of shit because the other batteries LCD display always and only displays the voltage of the battery NEVER the voltage applied.

Lastly, when connected in series, the batteries go out of balance pretty quickly (few minutes). Yes I have charged them fully individually.
one never stays at 13.5V. One of them will be at 13.5V while the other will be at 13.3V.


Oh also when even the smallest load (1Amp) is applied to the battery bank, the voltage will drop quite a bit, for example if they are at 13.3V, it'll drop to 13V.


Thanks heaps!

Please identify this Vendor/Retailer so everyone is aware of their BS.
You have been fed "some" Hooey ! There should be No Moisture in there unless a cell has vented, and if it has, it's not safe.
DIY'ers can drop a Desiccant Packet into a newly assembled box IF done in a humid environment.
An Unsealed Case "MAY" gain ambient moisture IF the temperature differentials are appropriate for it... You are NOT in the Deep Cold Regions so really not likely is it... Do you see condensation on things around you ?
The BMS' are also not configured properly...
LFP should never go below 2.5Vpc, so 10/20/40 volts relative to 12/24/48. Safe Cutoff should actually be 2.750Vpc.
It cannot exceed 3.650Vpc, so 14.6/29.2/58.4 Volts per pack, relative.
FACT IS, Most LFP will start to diverge beyond 3.425Vpc (13.7/27.4/54.8)

 

[A.Justice]

Please identify this Vendor/Retailer so everyone is aware of their BS.
You have been fed "some" Hooey ! There should be No Moisture in there unless a cell has vented, and if it has, it's not safe.
DIY'ers can drop a Desiccant Packet into a newly assembled box IF done in a humid environment.
An Unsealed Case "MAY" gain ambient moisture IF the temperature differentials are appropriate for it... You are NOT in the Deep Cold Regions so really not likely is it... Do you see condensation on things around you ?
The BMS' are also not configured properly...
LFP should never go below 2.5Vpc, so 10/20/40 volts relative to 12/24/48. Safe Cutoff should actually be 2.750Vpc.
It cannot exceed 3.650Vpc, so 14.6/29.2/58.4 Volts per pack, relative.
FACT IS, Most LFP will start to diverge beyond 3.425Vpc (13.7/27.4/54.8)

I suspect the vendor is Unisapower. The member joined yesterday, and has ONLY posted two messages, both try to "dispute" OP's claim.

That's not a good look if that is indeed the case.

 

[curiouscarbon]

water drops inside the battery box are normal for LiFePO4 batteries

water drops inside the battery box are NOT normal for LiFePO4 batteries​

water inside the case presents a risk to operation and safety.

 

[Supervstech]

water drops inside the battery box are normal for LiFePO4 batteries. I have cut voltax battery open and the water was pooling inside. They LCD measures the voltage which is the highest, this means if the battery is 12v and you apply any voltage higher than 12, the lcd will read the higher voltage. Vice versa, if you apply a voltage lower than 12v, the LCD will read 12v which is the highest.

Please list all brands you have tested with NORMAL water inside...
So we can avoid them!

 

[sircambridge]

i had a battery - Redodo 12V 100Ah refuse to charge after a full discharge, and it was stuck at 12.1V. If i tried to charge it, it would charge at 3A for about a minute and then stop. after a month of trying to figure out what was going on, i cracked open the lid to find a LOT of condensation inside the battery.

this battery was never anywhere wet, it was in a car trunk, and for a while inside my garage which has been very cold(sometimes below freezing) these past few months.

im in the process of drying it out right now. what could have happened?

 

[rodrick]

i had a battery refuse to charge after a full discharge, and it was stuck at 12.1V. If i tried to charge it, it would charge at 3A for about a minute and then stop. after a month of trying to figure out what was going on, i cracked open the lid to find a LOT of condensation inside the battery.

this battery was never anywhere wet, it was in a car trunk, and for a while inside my garage which has been very cold(sometimes below freezing) these past few months.

im in the process of drying it out right now. what could have happened?

The cold will not hurt it as long as you do not!!! Charge below 32 degrees 0c discharge can go lower but if you are using them I would keep them above 40 if possible just to be safe

the condensation is from trapped moisture during manufacturing most likely put some desiccant bags like referenced above once you get it dry

i wonder how many sealed units are like that kinda scary

 

[sircambridge]

The cold will not hurt it as long as you do not!!! Charge below 32 degrees 0c discharge can go lower but if you are using them I would keep them above 40 if possible just to be safe

the condensation is from trapped moisture during manufacturing most likely put some desiccant bags like referenced above once you get it dry

i wonder how many sealed units are like that kinda scary

yeah this is a crazy amount of moisture. I can tell the terminals inside the battery have some corrosion already from prolonged exposure to the moisture. I kind of want to open all my lifepo4 batteries just to see.

 

[Sylwood2]

I have opened a lot of Lifepo4 batteries from different manufactures and have seen lots of damage from moisture. Almost all of these are from condensation and not submersion. All of these are made in China (yes all) and it doesn't matter the conditions where they are assembled because there is not a single battery I have opened that was a complete seal. The tops are glued on with CA glue in a few places , leaving lots of places that are not sealed. most all of these batteries ,if not all , are from fishing boats that are exposed to the elements of weather but not direct rainfall. think bass boat battery compartments. I have seen cups full of water come out of some. In every case, the bms has to be replaced and corrosion cleaned. I think this battery will need the same. It does not take very much moisture to ruin a bms. I know this post is older but I couldnt tell if the problems you are having are on the battery with the moisture inside. moisture/corrosion damage on the bms will show lots of different problems.