Fogstar and Victron charger issue

[Ian_H]

Hi all
I have recently bought a fogstar 230Ah underseat battery and have a Victron bluesmart 30A mains charger. With the charger on the default lithium setting (14.2V) the battery bms does not get to 100%, and when the victron has finished the absorption stage the fogstar app was showing declining SOC eg 98%, 96%, 94% with each cycle. With the Victron settings changed to 14.4V, everything seems to work fine. Has anyone else seen anything similar?
Many thanks
Ian

 

[Gromett]

14.4v seems to be the setting.

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[Ian_H]

14.4v seems to be the setting.

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How do I charge my leisure battery? How does the heating work? What size terminal posts do I need? We answer these questions plus many more here...

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This is from your link....
We recommend Victron equipment is set to a Float of 13.5V and 14.2V Bulk.

 

[Whitebirdyman]

I am having a similar issue with a Topband 150Ah battery. I do not have a compatible mains charger so removed the fuse from the EBL to disable charging, but can use it on the gel setting if necessary, but have been told that it cannot fully charge lithium batteries.

On a recent 2 month trip, relying on the Victron solar charger and the Sterling B2B both on lithium setting, I noticed that after several weeks the maximum SOC was falling despite there being plenty of sun in Spain and several long drives. On querying this, I was advised to connect the mains charger, which input 14.4V and immediately reset the battery to 99% SOC without having time to do any actual charging. It did, however, reduce the maximum reported capacity from its usual 150Ah to 149.9Ah, not much of a drop but interesting that this happened. Discussions are still ongoing regarding whether this is a charger or battery issue.

 

[Gromett]

A quick point.
If you do not fully charge a battery then the SOC will fall over time.
No battery is 100% efficient, in that you cannot get out as much as you put in.
If you regularly use the battery without giving it a full charge then the SOC counter will get out of sync with reality.
It needs to be given a full recharge to reset it.

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[Gromett]

This is from your link....
We recommend Victron equipment is set to a Float of 13.5V and 14.2V Bulk.

I see you are having a conversation with them on FB. Good luck

 

[Lenny HB]

A Fogstar 105ah battery we fitted in Tam's Northernraider van charged to 100% with a Victron 30 amp IP22 charger set to default Lithium at 14.2v.

 

[Ian_H]

I am having a similar issue with a Topband 150Ah battery. I do not have a compatible mains charger so removed the fuse from the EBL to disable charging, but can use it on the gel setting if necessary, but have been told that it cannot fully charge lithium batteries.

On a recent 2 month trip, relying on the Victron solar charger and the Sterling B2B both on lithium setting, I noticed that after several weeks the maximum SOC was falling despite there being plenty of sun in Spain and several long drives. On querying this, I was advised to connect the mains charger, which input 14.4V and immediately reset the battery to 99% SOC without having time to do any actual charging. It did, however, reduce the maximum reported capacity from its usual 150Ah to 149.9Ah, not much of a drop but interesting that this happened. Discussions are still ongoing regarding whether this is a charger or battery issue.

Fogstar talked me through resetting the bms and advised cycling the battery to fully discharge (until bms cut off) and recharge fully 3 times. My 230Ah battery now shows a capacity of 239Ah, as predicted by Fogstar. I've no idea if our batteries use the same bms but you may need to do something similar.

 

[Ian_H]

I see you are having a conversation with them on FB. Good luck

Yes, Ben at fogstar is contacting EVE after reproducing the problem. I'm just trying to find out if it has affected all batteries, just the underseat, or just the latest batch of underseat models.

 

[DABurleigh]

have a Victron bluesmart 30A mains charger.

Ian,

I am mulling a Victron mains charger. Having had their 1200 and 2000 watt inverter chargers both gave a low-level eddy current hum when swiched on. If you wanted mains on you had to have the battery charger on. With my new van my head in bed will be close to the electrics and I want to avoid hums. Is your bluesmart 30A absolutely silent?

Dave

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[Ian_H]

Ian,

I am mulling a Victron mains charger. Having had their 1200 and 2000 watt inverter chargers both gave a low-level eddy current hum when swiched on. If you wanted mains on you had to have the battery charger on. With my new van my head in bed will be close to the electrics and I want to avoid hums. Is your bluesmart 30A absolutely silent?

Dave

In a word no! It hums quite loudly at 30A. The fan does seem to be silent. Via the app you can easily limit it to 15A either ongoing or for 8 hours. It is then much quieter but still not silent. However, it is sat on the bench and not screwed down which doesn't help.

 

[Lenny HB]

Ian,

I am mulling a Victron mains charger. Having had their 1200 and 2000 watt inverter chargers both gave a low-level eddy current hum when swiched on. If you wanted mains on you had to have the battery charger on. With my new van my head in bed will be close to the electrics and I want to avoid hums. Is your bluesmart 30A absolutely silent?

Dave

Not the Blue Smart but the 30 amp IP22 is noisy when charging at 30 amps.

 

[DABurleigh]

I don't object to some fan noise at full whack, which is limited in duration, but hum all the time the mains is on (and batteries just on float) isn't what I expected from Victron. Probably simply just having a switchable battery charger separate from the EHU supply to fridge, heating and hot water will do it for me.

 

[Guigsy]

I've got a Victron IP22 20A. It's silent most of the time. I've not noticed any hums. The fan does kick in if it's charging at 20A for a couple of hours straight. You can manually switch it to 10A so it runs silent. Or put it in night mode, which keeps the fan off so I think it runs 20A whenever it's cool enough?

 

[Ian_H]

I don't object to some fan noise at full whack, which is limited in duration, but hum all the time the mains is on (and batteries just on float) isn't what I expected from Victron. Probably simply just having a switchable battery charger separate from the EHU supply to fridge, heating and hot water will do it for me.

I've not been clear enough above, I think it is silent on float.

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[Ian_H]

I am having a similar issue with a Topband 150Ah battery. I do not have a compatible mains charger so removed the fuse from the EBL to disable charging, but can use it on the gel setting if necessary, but have been told that it cannot fully charge lithium batteries.

On a recent 2 month trip, relying on the Victron solar charger and the Sterling B2B both on lithium setting, I noticed that after several weeks the maximum SOC was falling despite there being plenty of sun in Spain and several long drives. On querying this, I was advised to connect the mains charger, which input 14.4V and immediately reset the battery to 99% SOC without having time to do any actual charging. It did, however, reduce the maximum reported capacity from its usual 150Ah to 149.9Ah, not much of a drop but interesting that this happened. Discussions are still ongoing regarding whether this is a charger or battery issue.

Hi
Did you get any further with this? I've heard from one other Fogstar owner who had the same symptoms which went away with a 14.4V setting.

 

[PaulandChrissy]

I set my mains charger and solar to 14.3. This charges to 100% without the BMS switching the charging mosfets off and on repeatedly. This also gives the BMS plenty of time to balance the cells.
When the vans not being used, I turn it down to 13.5 to prevent the batteries being stored at 100%

 

[AdrianChen]

Odd issue this, for the Victron do you have a shunt/Smartsense wired in to tell the charger via SmartNetwork (and Sterling equivalent) the actual voltage at the terminals?

I don't know how the Fogstar BMS calculates when the battery is at 100% but it presumably uses a mix of current flow in and cell voltage?

So I wonder if the output voltage the Victron/Sterling are delivering is compensating for any drop through the cables/connections (and inside the battery case etc to the BMS) and if not what effect this might have on the cell balance, which would also show up on the app I guess.

PS, I know nothing so please ignore if this is stupid!

 

[headlight]

Hi all
I have recently bought a fogstar 230Ah underseat battery and have a Victron bluesmart 30A mains charger. With the charger on the default lithium setting (14.2V) the battery bms does not get to 100%, and when the victron has finished the absorption stage the fogstar app was showing declining SOC eg 98%, 96%, 94% with each cycle. With the Victron settings changed to 14.4V, everything seems to work fine. Has anyone else seen anything similar?
Many thanks
Ian

I have recently got a Fogstar 230AH, not the underseat but I would imagine it has the same BMS.
I set my Victron MPPT and Sterling B2B to 14.2v charge and 13.5v float as recommended by Fogstar and Vanbitz.
My battery charges to 100% SOC and 230AH fine.
What I find is that the app SOC and AH Drifts away from being correct and shows more SOC and AH than the battery actually has, as confirmed by my shunt, as the BMS can't detect small loads of 1 amp or under.
For example at the moment the app is showing 92% SOC but the shunt is showing 80%.
When I next use the van the B2B will fully charge the battery whilst driving to our destination and the app SOC will reset to 100%.
It will then drift away from being correct again as things like running led lights will not register a drain.
I use the shunt to monitor SOC and AH not the app.

 

[Guigsy]

I find

I have recently got a Fogstar 230AH, not the underseat but I would imagine it has the same BMS.
I set my Victron MPPT and Sterling B2B to 14.2v charge and 13.5v float as recommended by Fogstar and Vanbitz.
My battery charges to 100% SOC and 230AH fine.
What I find is that the app SOC and AH Drifts away from being correct and shows more SOC and AH than the battery actually has, as confirmed by my shunt, as the BMS can't detect small loads of 1 amp or under.
For example at the moment the app is showing 92% SOC but the shunt is showing 80%.
When I next use the van the B2B will fully charge the battery whilst driving to our destination and the app SOC will reset to 100%.
It will then drift away from being correct again as things like running led lights will not register a drain.
I use the shunt to monitor SOC and AH not the app.

I've found the same thing. While you're actively using the van, the SOC from the BMS is pretty accurate and it largely agrees with my Victron shunt. The key is that it's getting up to 100%, so gets a chance to recalibrate, and that most of the loads are pretty high, so the low sensitivity of the BMS doesn't matter.

But when the van has been sitting on the drive for a few weeks through the winter and the solar isn't bumping it up to 100% each day, the BMS drifts () and can massively over estimate how much is left in the battery. A full charge before we go away (which we do to pre-chill the fridge anyway) sorts it out.

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[Pausim]

Hi all
I have recently bought a fogstar 230Ah underseat battery and have a Victron bluesmart 30A mains charger. With the charger on the default lithium setting (14.2V) the battery bms does not get to 100%, and when the victron has finished the absorption stage the fogstar app was showing declining SOC eg 98%, 96%, 94% with each cycle. With the Victron settings changed to 14.4V, everything seems to work fine. Has anyone else seen anything similar?
Many thanks
Ian

14.2V is on the low side for most Lipo batteries. My Votronic B2B instructions listed the battery voltages for various makes of battery and most were either 14.4V or 14.6V, the Victron LFP was one of only 2 types listed at 14.2V but this would explain why it is the default setting on their charger. Many users choose 14.2V because under charging is better than over charging, the absorption stage is not needed and it would be better to drop immediately to a lower voltage maintenance charge of about 13.6V.

 

[headlight]

Hi all
I have recently bought a fogstar 230Ah underseat battery and have a Victron bluesmart 30A mains charger. With the charger on the default lithium setting (14.2V) the battery bms does not get to 100%, and when the victron has finished the absorption stage the fogstar app was showing declining SOC eg 98%, 96%, 94% with each cycle. With the Victron settings changed to 14.4V, everything seems to work fine. Has anyone else seen anything similar?
Many thanks
Ian

How many cycles has the battery done ?

 

[headlight]

14.2V is on the low side for most Lipo batteries. My Votronic B2B instructions listed the battery voltages for various makes of battery and most were either 14.4V or 14.6V, the Victron LFP was one of only 2 types listed at 14.2V but this would explain why it is the default setting on their charger. Many users choose 14.2V because under charging is better than over charging, the absorption stage is not needed and it would be better to drop immediately to a lower voltage maintenance charge of about 13.6V.

Fogstar recommend 14.4v and 13.6v unless the charging source is Victron when they recommend 14.2v and 13.5v.
I have charged at 14.4v as that is what the Fogstar mains charger charges at which I used to put a couple of cycles on the battery before I fitted it.
My battery charges to 100% SOC and 230AH whether charged at 14.4v or 14.2V.

 

[PaulandChrissy]

The BMS on lithium batteries in general does not register very low amperage’s. This means that if you are discharging say 0.2amps, it will not register it and the SOC will drift off. Once fully charged again it will reset back to 100% and all is fine again. The SOC on the BMS display is only a guide. Much better to have a good guilty shunt which is far more accurate.

 

[Ian_H]

Fogstar recommend 14.4v and 13.6v unless the charging source is Victron when they recommend 14.2v and 13.5v.
I have charged at 14.4v as that is what the Fogstar mains charger charges at which I used to put a couple of cycles on the battery before I fitted it.
My battery charges to 100% SOC and 230AH whether charged at 14.4v or 14.2V.

My fogstar 230Ah has done 18 cycles now. After a week away with no ehu I charged it up today with the mains to see how far out the bms SOC was, and retry with the victron absorption voltage at 14.2V.
So it started with the SOC showing 63% and 150.2Ah left.

After bulk charging and a couple of hours in absorption mode the current had been zero for ages, and the shown SOC was 98% and 232.9Ah.

I changed the absorption voltage to 14.3V from 14.2V and immediately the SOC went to 100% and 238.7Ah.

Over the charge period before the reset to 100% the bms thought it had received 238.9-150.2 = 88.9Ah.
The victron charger thought it had sent 90.3Ah. I guess if the small difference is real, it could be accounted for in cable and other losses.
Since the bms didn't need to receive as many Ah as it thought it needed, I think in this case the bms SOC was an underestimate, rather than an overestimate. Maybe this could be due to a sun free week in Yorkshire, and solar charging being less than the bms detection limit for significant lengths of time?
As others have described above, the approach I am developing is to fully charge before or during the start of the break so the bms SOC starts as accurate. Over trips of about a week I have seen the bms SOC be out (high and low)
by around 10Ah (5%), which I don't need to be concerned about. I keep an eye on the voltage too, less than 13.1V would get my attention.

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[Guigsy]

I think if you're actively using the van, over a couple of weeks, the difference will be negligible and irrelevant. It's perfectly good enough to rely on.

Over December and January, the van got very little use. The BMS still said it was 95%. The Victron shunt said it was nearer 30%. And when I charged it, the amount of Ah that the charger said I'd pumped into it was about 70%. The issue is my van has quite high parasitic loads, but they are too small for the BMS to register. So the drift adds up. But it's only an issue in the depths of winter.

Over the last month, it's not been an issue as the solar has been bouncing the battery back to fully charged. So the BMS and the shunt get reset and remain in agreement.