LiFePO4 at 11.71v

The Artilleryman

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Checked my KS Energy hab battery and it's showing 11.71v 82% SOC, doesn't seam right to me.
 
Checked my KS Energy hab battery and it's showing 11.71v 82% SOC, doesn't seam right to me.

I wouldn’t be worried about the SoC reading (they tend to be go awry) but the 11.71V reading looks concerning.

I’d be inclined to get that on charge soonest.

Are you able to measure the voltage at the terminals. That’ll help identify if it’s a battery, or a BMS, issue.

Ian
 
I wouldn’t be worried about the SoC reading (they tend to be go awry) but the 11.71V reading looks concerning.

I’d be inclined to get that on charge soonest.

Are you able to measure the voltage at the terminals. That’ll help identify if it’s a battery, or a BMS, issue.

Ian
Voltage across the terminals is the same.
 
Voltage across the terminals is the same.

Just checked my BMS settings and I have the low voltage cutoff at 10V.

If you haven’t done so already, I’d be giving it a full charge.

Ian

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Yes, it's on charge, but only from the standard in built charger.
 
Yes, it's on charge, but only from the standard in built charger.
That’s ok, slow charge even better coming from low SOC. At 11.71v it’s about 2.92v per cell. Bellow 3v, it’s not much energy left, less than 5%. But , it’s still safe up to 10v when bms will disconnect. Better not to get there, and you are doing ok to charge it up.
 
Getting 5.5a charge from onboard charger. I've got a Victron IP22 12/15 waiting to be fitted, problem being the battery terminals are round post brass, rather than the preferred bolt type and cannot make up anything to easily connect it the battery - no crock clips or eyelet heavy enough - and I'm unable to drive at the moment so can't get anything from screwfix etc. tomorrow.
 
Getting 5.5a charge from onboard charger. I've got a Victron IP22 12/15 waiting to be fitted, problem being the battery terminals are round post brass, rather than the preferred bolt type and cannot make up anything to easily connect it the battery - no crock clips or eyelet heavy enough - and I'm unable to drive at the moment so can't get anything from screwfix etc. tomorrow.
5.5 a on a flat battery, theres something wrong with that. Is it set correctly?

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have you checked what its putting in? There must be a reason its run flat, or has it been left a long time ?
Fitted new end of November charged to 90% SOC then discharged to 81% (internal lights), then electrics shut down and 12v batt. fuse pulled on BCA PDU, so should not be discharging. Checked every couple of weeks via app. then health problems and cold weather stopped me checking - need to be next to MH for BT to work.

I wonder if during the 2 very cold spells we had weather this turned a heater of some sort on, only thing I can think of.
 
My lithiums always cock up the smart shunt when they get cold.

They were reading 100% yesterday on about the same voltage. They are about 50% as I checked them before it went cold.

I would warm it up if you haven’t already and don’t charge it in freezing conditions whatever you do.

The voltage and SOC readings are always really out when they are cold, I think it’s the BMS somehow.
 
5 Celsius and unlikely to go much lower.

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I also have a KS battery the 200Ah under seat version, I had been in and out of the van getting ready for a trip and as the battery set up is new to me I had been checking the readings virtually every time I went in van.
Checked on the app before I shut it down and was reading 85% SOC, next morning day before we are due to go away back out to van to continue preparations and tried to switch lights on and nothing, put meter across terminals and zero, connected my Victron IP22 10A and all that did was to power the interior lights, then remembered seeing a report on here of someone with a different make of battery having a similar occurrence and they "jump" started the battery with a simple 12 volt kick from a Lead acid which I did and it came alive.
When home the van lives in its own house so no charge from solar.
With the battery now alive it read 11.64 volts across the terminals and that also allowed the bluetooth connection with the BMS which showed 85%SOC. battery temp showed 8 degrees, cells were 2905, 2906, 2916 and 2924
I contacted KS who responded very quickly but simply said the battery was flat and to fully charge until voltmeter showed 14.4 or thereabouts volts, I can't understand how the battery could have apparently discharged with no use, I left on charge for 36 hours and then app showed 100% SOC and 14.1 volts.
We've been away now for 2 weeks and it has and is performing perfectly, I have 470w of solar and 30a B2B.
 
To be honest, I don't agree with a couple of thing there
My lithiums always cock up the smart shunt when they get cold.

They were reading 100% yesterday on about the same voltage. They are about 50% as I checked them before it went cold.
That makes little sense. It could suggest there is a fault somewhere.
Alternatively, if the batteries are shutting down when cold (they shouldn't), you might be resetting the Smartshunt SOC reading to 100% when they wake up again. There is a new option on the Victron Smartshunt that allows it to remember the SOC on a reset. Worth setting that so you don't get sprurious 100% SOC resets.

I would warm it up if you haven’t already and don’t charge it in freezing conditions whatever you do.
Fair enough. the batteries BMS should provide protection, but that is another precaution that can be taken. EXCEPT ... if the batteries have heaters, the chargers should be left on, otherwise they will never come on and warm the battery
The voltage and SOC readings are always really out when they are cold, I think it’s the BMS somehow.
This should not be the case. it is either a faulty or a rubbish (same thing) BMS.
 
Fitted new end of November charged to 90% SOC then discharged to 81% (internal lights), then electrics shut down and 12v batt. fuse pulled on BCA PDU, so should not be discharging. Checked every couple of weeks via app. then health problems and cold weather stopped me checking - need to be next to MH for BT to work.

I wonder if during the 2 very cold spells we had weather this turned a heater of some sort on, only thing I can think of.
You can't really rely on the BMS SOC when brand new until you have done a FULL charge so you are on a known charge position. By charging to only 90% as reported by the BMS you cannot actually be confident that is the true State of Charge. And with Lithium, above around 20% or so SOC, it is very hard to tell the level of charge looking at voltage as the discharge voltage curve is so level.
I would suggest you out the battery on charge until the charger stops putting any current into the battery and ignore the SOC reporting. once the charger stops charging, the battery should be full and then you know where you stand.
 
My KS Energy batteries go to sleep when not been used for some hours. Turning on led lights is not enough to wake them up but a prod on the electric step or water pump instantly wakes them up and shows 13+ volts. I do find the built in app is not very accurate.
 
I have KS battery's and I like to think I was a pioneer in them in that I was one of the first to fit them before blue tooth etc was fitted
My 2x120 ah have a small window on top which shows temp and soc (I think) but the battery's are buried in cupboard so I can't see them and therefore never look at them.
I rely totally on a votronic smart shunt which has never (in 5 yrs) let me down. I always know my battery voltage and SOC. It calculates input against output very efficiently to lets me know where I stand
I believe (flak jacket and hard hat fully in place) that leisure vehicle users put too much reliance and faith in so called blue tooth technologie.
One has a battery at 100%charge.. how do we know.. because we have just charged it . And we know size of battery so we know how much amps/kwatts said battery holds.we then proceed to discharge battery.. x amps.??
At same time solar is inputting amps into battery .. no problem
My votronic is clever enough to work out.. 5amp discharge plus 7amp charge =2amp charge.. which shows on the display.

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I have KS battery's and I like to think I was a pioneer in them in that I was one of the first to fit them before blue tooth etc was fitted
My 2x120 ah have a small window on top which shows temp and soc (I think) but the battery's are buried in cupboard so I can't see them and therefore never look at them.
I rely totally on a votronic smart shunt which has never (in 5 yrs) let me down. I always know my battery voltage and SOC. It calculates input against output very efficiently to lets me know where I stand
I believe (flak jacket and hard hat fully in place) that leisure vehicle users put too much reliance and faith in so called blue tooth technologie.
One has a battery at 100%charge.. how do we know.. because we have just charged it . And we know size of battery so we know how much amps/kwatts said battery holds.we then proceed to discharge battery.. x amps.??
At same time solar is inputting amps into battery .. no problem
My votronic is clever enough to work out.. 5amp discharge plus 7amp charge =2amp charge.. which shows on the display.
The bluetooth bit is a method of communication, not a method of calculation. The first is allowing the presentation of the second, and nothing else.
You are not using bluetooth for find the battery information because you are looking at a wired display. it doesn't make it any more accurate by doing so.
I can do the same as you for my batteries by looking at the wired display on my Victron BMV. I can also see the same information by connecting to the monitor via a Smart App on the phone. makes it easier to use but has no impact on the data.
 
The bluetooth bit is a method of communication, not a method of calculation. The first is allowing the presentation of the second, and nothing else.
You are not using bluetooth for find the battery information because you are looking at a wired display. it doesn't make it any more accurate by doing so.
I can do the same as you for my batteries by looking at the wired display on my Victron BMV. I can also see the same information by connecting to the monitor via a Smart App on the phone. makes it easier to use but has no impact on the data.
Oki doki...I had to read that 3 or 4 times and I believe you are indeed agreeing with me ,(however probably wrong) .
So are you saying blue tooth is only displaying (through Internet connections) what the battery is telling the votronic display direct thru the fitted smart shunt.
My battery's.. Once fully charged will show me.. via Votronic Smartshunt Computor Display at all times voltage and SOC.
So why do I need bluetooth??
 
Oki doki...I had to read that 3 or 4 times and I believe you are indeed agreeing with me ,(however probably wrong) .
sorry, no, I am not :)
So are you saying blue tooth is only displaying (through Internet connections) what the battery is telling the votronic display direct thru the fitted smart shunt.
My battery's.. Once fully charged will show me.. via Votronic Smartshunt Computor Display at all times voltage and SOC.
So why do I need bluetooth??
why do YOU need bluetooth? You don't. But if the device that is performing the calculations has no display and relies a Smart App and relays that information via Bluetooth, then that is when Bluetooth would usually be needed.
The point is Bluetooth is just another form of communication. Your batteries have a display built into them (which you never look at as too awkward). It is very rare to see a display physically on a battery as that information is now relayed via bluetooth as ... guess what ... it is a lot less awkward for the user. Because it is relayed via bluetooth does not make it worse, it makes it more convenient.

My Batteries have no display, but they have bluetooth. If I want to look at the Battery info directly, I can run a phone app and see them. you have dig around in a cupboard to see the display on your batteries. I win :)
However, you chose instead of that to use a Votronics Shunt with a Monitor so you can see the data, albeit external to the Battery (I am assuming here). I can do exactly the same with the Victron BMV, again external to the battery. However I chose to mount the BMV Monitor in an external Locker where my electrics are housed. So for ease of use reading the physical Monitor, YOU win :)
But .... I can connect to the BMV Monitor via an App on the phone using Bluetooth, or via a App or Browser on my Phone or Laptop using the Internet, so I can see the battery state of charge, current in & out, etc in the Motorhome, in the Sitting Room, in the Bath, wherever. I'll take that win :D
 
Thanks for the comments and help, my main concern is What caused the battery to discharge down to a level where the bms shut the battery down.
The battery is still on charge at 5a from the onboard charger, so should be fully charged by lunch time - will check battery voltage is 14.1v or there about. Will then physically disconnect the battery and monitor via BT and multi meter.

I'm well aware of the charge/discharge characteristics of non LA batteries as I started model car racing with 1200 mah SC ran right through to 3600mah NiMH. We abused these as we wanted the absolute max. charge and they would then be fully discharged in 300 seconds.
 
Thanks for the comments and help, my main concern is What caused the battery to discharge down to a level where the bms shut the battery down.
The battery is still on charge at 5a from the onboard charger, so should be fully charged by lunch time - will check battery voltage is 14.1v or there about. Will then physically disconnect the battery and monitor via BT and multi meter.

I'm well aware of the charge/discharge characteristics of non LA batteries as I started model car racing with 1200 mah SC ran right through to 3600mah NiMH. We abused these as we wanted the absolute max. charge and they would then be fully discharged in 300 seconds.
I think Hoovie has made a good point about the accuracy of shunts but the question for me is wh your charger is only putting such a low charge in? It should be maxing.

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Thanks for the comments and help, my main concern is What caused the battery to discharge down to a level where the bms shut the battery down.
The battery is still on charge at 5a from the onboard charger, so should be fully charged by lunch time - will check battery voltage is 14.1v or there about. Will then physically disconnect the battery and monitor via BT and multi meter.

I'm well aware of the charge/discharge characteristics of non LA batteries as I started model car racing with 1200 mah SC ran right through to 3600mah NiMH. We abused these as we wanted the absolute max. charge and they would then be fully discharged in 300 seconds.
Very simple, cold activated the heater pads and drained the battery without having a charger connected. The shunt can’t see the heater pads to register a draw to account for, because it’s before the shunt on the battery side. If the heater pads would been after the shunt, like any other load, your shunt would of told you that your battery is going down.
Moral, if you have heaters, leave charger on, without restricting charge on cold.
 
I think Hoovie has made a good point about the accuracy of shunts but the question for me is wh your charger is only putting such a low charge in? It should be maxing.
Because that’s the size of the charger,
 
Very simple, cold activated the heater pads and drained the battery without having a charger connected. The shunt can’t see the heater pads to register a draw to account for, because it’s before the shunt on the battery side. If the heater pads would been after the shunt, like any other load, your shunt would of told you that your battery is going down.
Moral, if you have heaters, leave charger on, without restricting charge on cold.
If you are referring to lithium batteries with integral heaters, it would be a very strange (read poor) design to have the heaters to be powered by the battery and activate at low temp. That would be very wasteful of battery power as there is no need to heat the battery to above freezing if there is no charging available.
I would be disappointed (although not that surprised) to hear some batteries have a poor setup like this. Neither of the Lithium batteries I have had with Heaters work that way - the heaters only come on when cold AND there is charging over a certain level (and below that level the charger goes to the cells direct - but that is a different conversation about actual charging when cold).

If you are talking about external add-on DIY heaters, then down to how the installer did this and hopefully they fitted them so the -ve is on the load side of the shunt (if not, they were not properly installed) and only active when charging is available.
 
Thanks for the comments and help, my main concern is What caused the battery to discharge down to a level where the bms shut the battery down.
The battery is still on charge at 5a from the onboard charger, so should be fully charged by lunch time - will check battery voltage is 14.1v or there about. Will then physically disconnect the battery and monitor via BT and multi meter.

I'm well aware of the charge/discharge characteristics of non LA batteries as I started model car racing with 1200 mah SC ran right through to 3600mah NiMH. We abused these as we wanted the absolute max. charge and they would then be fully discharged in 300 seconds.
Point about the onboard charger ... Is it really a 5A charger you have and is this really a primary charger for the batteries when hooked up?
That is a very small charger for the size of battery and it means it will be going at full capacity for a very long time. Generally running something at its full rate will result in that device getting very hot and either throttling back or overheating and failing. If it were me, I would be getting a more powerful charger without any doubt, and I would keep an eye on the current one to check it is still operational and checking what the charge current is.

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