Leisure Battery - Is it faulty? BM2

[IestynD]

Hi all,

I use BM2 to monitor my starter and my leisure battery (2 seperate BM2s).
I checked the starter battery the day after we'd had a 1 night camping trip and it showed 7% - almost flat!! Which is odd as the battery is less than a year old and clearly we had driven home from the camping trip. The alternator is working as BM2 shows the spike to 14.4V for the durration of the trip. I *think* the issue with the starter battery is the Dash Cam i have fitted. Its hardwired in and I suspect over a 14 hour window of no engine charge it almost drains the starter battery! I can accept that, and i need to tweek the BlackVue settings to make it not do a parking mode.

@Dellmassive i think you use a Ring door bell - whats that like for power usage over say a 20 hour window does that drain your battery? Its obviously not a dash cam but obviously good at "parking mode". The blackvue has a constant state of monitor, g sensors, and cloud connected when on the drive so pretty load heavy i would think!

So onto the leisure battery. I suspect over winter it got drained when the van was used on the drive for the camp out to help out and other adventures on the drive for the kids - diesel heater and LED lights used. Battery not looked after and left to discharge flat!
Once i realised what i'd done I charged it properly with my new Victron charger... i even fitted a Victron Battery protect 65amp... this i don't think is working properly as it never disconects the load even when the leisure battery is showing as dead.

Yesterday i removed the passenger seat, removed the leisure battery from the van and charged it on the bench in the garage.
I have my BM2 connected to it and in less than 24 hours its dropped from 100% charged to 70% (12.73V to 12.43) There is only the BM2 attached to the battery noting else! Is my leisure battery ruined?
Its a Yuassa 7000 series (75ah, 700A). Model YBX7096. Its approx 2 years old.

Some pictures from the BM2:

Battery fully charged yesterday at 12:02




As you can see i lost some history from the BM2 as it got disconnected when removing the charger clamps, but you get that its fully charged:



This morning however its down to 70%....
Its just sat on the bench in the garage not too cold...




A steady decline....


This picture shows a proper flat leisure battery - the Victron Battery Protect didnt do anything!



Finally this is a typical usage week of my van:
Sept 10th, it gets a good charge from the alternator... then in 2 days its pretty much flat again.


So, do i replace it with a Lithium and a Sterling DC to DC charger? (currently a relay Its a bit snug under the seat already but i think i could fit the DC to DC under the drivers seat and run the cables back... not looked at that just yet.



Any opinions very welcome.

Thank you

 

[Dellmassive]

I *think* the issue with the starter battery is the Dash Cam i have fitted. Its hardwired in and I suspect over a 14 hour window of no engine charge it almost drains the starter battery! I can accept that, and i need to tweek the BlackVue settings to make it not do a parking mode.

- yes a dash cam will flatten a 100ah battery in 24/48 hrs depending on the settings.

look at running it off the LB.

and tweek the motion detection and frame rate settings.

 

[Higgidav]

My BM2 on my starter has failed after giving odd readings for a few months. I checked the readings against my multimeter so I knew the BM2 was going wrong. I’m going to swap it with another when I get back home from my current trip.

 

[Dellmassive]

@Dellmassive i think you use a Ring door bell - whats that like for power usage over say a 20 hour window does that drain your battery? Its obviously not a dash cam but obviously good at "parking mode". The blackvue has a constant state of monitor, g sensors, and cloud connected when on the drive so pretty load heavy i would think!

- my RING doorbell camera in the van, (two of them) are battery powered - ie not fed from the van.

i just charge them up once a week or whenever.

but they DO conect to the vans WIFI, that IS powered 24/7 from the LB.

i run a LIFEPO4 so i get much longer run time.

if there is lots of movement then there is more wifi usage

 

[Dellmassive]

So onto the leisure battery. I suspect over winter it got drained when the van was used on the drive for the camp out to help out and other adventures on the drive for the kids - diesel heater and LED lights used. Battery not looked after and left to discharge flat!
Once i realised what i'd done I charged it properly with my new Victron charger... i even fitted a Victron Battery protect 65amp... this i don't think is working properly as it never disconects the load even when the leisure battery is showing as dead.

- it will do if its set and wired correct.

can you post a couple of pics and screenshot of the units settings in Victron connect?

 

[IestynD]

- i will do if its set and wire correct.

can you post a couple of pics and screenshot of the units settings in Victron connect?

Screen shot not available its not BlueTooth enabled, it relies on a jumper to set the limits!
I'll get some better pics of the wirring setup.

Thank you

 

[Dellmassive]

Yesterday i removed the passenger seat, removed the leisure battery from the van and charged it on the bench in the garage.
I have my BM2 connected to it and in less than 24 hours its dropped from 100% charged to 70% (12.73V to 12.43) There is only the BM2 attached to the battery noting else! Is my leisure battery ruined?
Its a Yuassa 7000 series (75ah, 700A). Model YBX7096. Its approx 2 years old.

- yes. no. maybe.

dont pay to much attention to the BM2 percentage readout. - its a guestimate at best.

its better to look at the voltage trend over time.

you can now do a 7day and 14day plot. - can you post some 7day plots.

....


is the battery plain LEAD or AGM.

AGMs have a rest voltage.


the battery could be low - ie a low SOC or SOH.

 

[IestynD]

My BM2 on my starter has failed after giving odd readings for a few months. I checked the readings against my multimeter so I knew the BM2 was going wrong. I’m going to swap it with another when I get back home from my current trip.

I've just ordered a "Victron (Love their stuff) Energy Smart Battery Sense Voltage and Temperature Sensor". I plan on using it to monitor battery voltage on the leisure battery. It will lend itself to the new Lithium battery as and when i get it.

Thank You

 

[Dellmassive]

this plot shows the battery running flat over 2 days.





you need to measure what the current flow is to determin if its current that dropping the battery or . . .

if no current flow then its the battery SOH has gone.

 

[Dellmassive]

you 100% need to swap out that relay for a DC-DC charger.






see here:

• 
  DC-DC:
• Dc-dc Charger (for Leisure Battery) -- How I Done It --
• Charging Starter and Leisure batteries with same charger - Victron
• Stop/start...regen...smart Alternator... Dc-dc Charger For Leisure Battery Or Not?

 

[Dellmassive]

again . . upgrading to a LIFEPO4 battery will also help.

once you have fitted a DC-DC.

you will get twice the run time. . . . and a quicker charge.






more info here:

• LIFPEO4:
• Lithium Lifepo4 12v Batteries -- Time For An Upgrade ? --
• Valence U27-12XP Lifepo4 Lithium Battery -- How We Done It --
• SUBZERO - low temperature lithium battery -- How We Done It --
• 12v Lithium Leisure Battery Box 138Ah 1766Wh -- How I Done It --
• Awesome-3-in-1-battery-bank -how-i-done-it.
• Solar-Generators - How i Done it -

.

 

[Dellmassive]

I've just ordered a "Victron (Love their stuff) Energy Smart Battery Sense Voltage and Temperature Sensor". I plan on using it to monitor battery voltage on the leisure battery. It will lend itself to the new Lithium battery as and when i get it.

Thank You

look at getting a "victron smart battery shunt" (a cheaper version of the victron BMV-712 - but without the screen)

that will accurately show you the power (current) going in/out of the battery.


it will also give you an accurate 0-100% SOC.

more info here:

Battery Monitoring -- How I Done It --

Battery Monitoring -- How I Done It -- Part #1 Battery monitoring is a very important part of your 12v system . . . . whether its just the vans starter battery or your leisure setup keeping an eye on the power in your battery bank will keep you from breaking down and make sure your weekends...

www.t6forum.com

...

https://amzn.to/3oUHtIs

 

[IestynD]

- yes. no. maybe.

dont pay to much attention to the BM2 percentage readout. - its a guestimate at best.

its better to look at the voltage trend over time.

you can now do a 7day and 14day plot. - can you post some 7day plots.

....


is the battery plain LEAD or AGM.

AGMs have a rest voltage.


the battery could be low - ie a low SOC or SOH.

7 day plot in the original post - more included below:

Pretty sure its AGM...

this plot shows the battery running flat over 2 days.



View attachment 132855

you need to measure what the current flow is to determin if its current that dropping the battery or . . .

if no current flow then its the battery SOH has gone.

Thanks for looking at this - I really apprecaite it.

Dumb question... how do i determin if its current that dropping that charge status or the battery health. Do i need a clamp meter? (i am happy to buy some new tools/testers).

At the moment the battery is on the bench and state of charge is falling off.... (according to BM2).
Nothing else connected to it.

Thanks

 

[Dellmassive]

A few examples of my Victron shunt on van.


.



.

 

[IestynD]

I just wish Victron did a Dc to DC with their MPPT input on it as well instead of having two units.
That with the smart shunt would be a setup worthy of any man!

 

[Insert Coin]

I find the whole VW leisure battery charging a bit of a mystery, but with my leisure battery I have the following -

WiFi dongle, BM2 and Webasto remote controller which are on 24/7 and my factory leisure battery never goes flat, it barely drops at all over a 7 day period.
The only time I’ve had it go flat was when I left a 12v cooler on for 36 hours, this killed the battery so I’ve got a like for like replacement now.

My other BM2, Ice install and Garmin dash cam with parking mode are on the starter battery and again this battery rarely drops day to day or week to week.

And I do have that crappy Bluemotion stop/start disabled which can’t be good in the long term for batteries?

 

[Dellmassive]

Dumb question... how do i determin if its current that dropping that charge status or the battery health. Do i need a clamp meter? (i am happy to buy some new tools/testers).

- the best option is a hard wired shunt.

other Toys include.

clamp meter:

Clamp Meters

Any recommendations for clamp meters? They have been mentioned in a few threads but I can’t find suggested products. Suitable for small mA measurements with dc in the van and elsewhere and also if possible up to mains ac. I’m not sure how much I need to spend for a tolerably decent one with the...

www.t6forum.com

.

12v battery tester:

https://amzn.to/3lyvizd

 

[Dellmassive]

i fitted two smart shunts to my mobile battery boxes . . . see here:

12v Lithium Leisure Battery Box 138Ah 1766Wh -- How I Done It --

12v Lithium Leisure Battery Box 138Ah 1766Wh -- How I Done It -- It's about time that I got this long-overdue project sorted out. The missing parts are on order and completion is in sight . . . . . . . . ready for the Post Pandemic 2020 Camping Trips (Hopefully) This is where it started. p1...

www.t6forum.com

.

 

[IestynD]

Bloody hell that escalated.

£108 for a smart shunt, and £40 for a clamp meter!
Small fortune being spent!

Next it will be the Lithium battery and a DC to DC charger.... Come on Victron get a DC to DC with MPPT built in!!!

@Dellmassive THANK YOU. You have helped me spend some money today....
I mean you have helped me learn about smart shunts and whats available to check.

 

[Dellmassive]

that battery is an "EFB" battery,

its still SLI, its a cheaper version of an AGM battery.

so better than a standard SLA, but not as good as an AGM.

and defo not as good as an Lifepo4.






+++

all SLA batteries can be damaged by running them flat too many times,

or not fully charging them up all the time.

SLA batteries like to be 100% SOC all the time.

running them flat or low reduces the SOH and the ability to fully recharge.

so they can loose health rapidly.



have you got a decent mains powered smart charger? - try the full 24hr charge?


more on chargers here:

Battery Chargers - How I Did It -

Battery Chargers - How I Did It - So its that time of year again, cold, rainy. . . . . . . flat battery =[ This time we look at Battery Chargers. Our vans will most likely come with a AGM style starter battery, for this type of battery we need a "Smart Charger" . . . . but what does this...

www.t6forum.com

.