BN 154ah Lithium and NL Battery box charging

[deanversfeld]

I've had the NL Battery box for a couple years now, and always had a 100ah lead acid in it, with its primary use of running my fridge and camping lights when going camping off/on grid.

As time progressed, I added a Victron 75/15 MPPT to the NL box, and I charged the system via following:
1. On AC via Victron blue smart 12v/15A (via the NL5 charging connection on the NL box)
2. While driving 12v socket in the back of my Amarok into the NL box via red BH
3. Solar while camping through the 75/15.

Happy days...all worked well until my lead acid started giving up the ghost, and I decided to buy the Blue Nova 154ah 2kw lithium for a bit more capacity 2 months ago.

Took the old lead acid out, replaced it with the new BN 154ah, changed the setting on my Victron 12v/15A charger to li-ion, and it should all work fine...right? Now I have to say while charging on AC I have always used the NL5 port on the NL battery box that is connected to my Victron 12v/15A charger, and its worked like a bomb, puts in bulk amps when low, and switches over the float when full. Again...happy days.

What Im finding with the new BN 154ah installed, is that when charging through the NL5 port using the Victron AC charger, it only loads the battery to 13.4v, and then kicks over to float. On the BN website the data sheet indicates it should get to 14.2 and float at 13.9v. Had me stumped until this weekend I stupidly realized I could also charge directly on the the battery terminals, and the Victron AC charger put the battery to 14.1v straight away, and floated at 14v. Now this has me confused as to where the problem lies, as Im almost immediately ruling out the battery, as well as the charger. Could it be the wiring in the NL battery box where there is some kind of voltage drop, but if its a voltage drop, why does the charger stop charging at 13.4v? I've also just come back from a hot Kgalagadi trip where my fridge was almost constantly running at -5 while driving and the loading of the battery via 12v vs the fridge draw was almost identical, which also has me thinking if there is an issue with the box somewhere. With the Victron smart 75/15 I was able to monitor the battery voltage while driving and it never once got over 13.3v, not saying its related but Im out of idea's.

All comments and suggests are welcome as to where to troubleshoot please......

[Fluffy]

Bump for the morning.

[the_terrible_triplett]

Took the old lead acid out, replaced it with the new BN 154ah, changed the setting on my Victron 12v/15A charger to li-ion ...

Did you mean Smart Lithium (Lifepo4) or li-ion?

Because:
Lithium-ion (Li-ion) battery differs from a lithium iron phosphate (LiFePO4) battery.

Blue Nova 154aH seems to be Lifepo4?

I checked the 75/15 settings under Demo.
You can set the settings to User Defined.
Then you can set the exact voltages for Bulk and Float as per BN.

[deanversfeld]

Did you mean Smart Lithium (Lifepo4) or li-ion?

Because:
Lithium-ion (Li-ion) battery differs from a lithium iron phosphate (LiFePO4) battery.

Blue Nova 154aH seems to be Lifepo4?

I checked the 75/15 settings under Demo.
You can set the settings to User Defined.
Then you can set the exact voltages for Bulk and Float as per BN.

Correct yes TTT, wherever I have used the word lithium, just replace it with LiFePO4.

Ill have a look at my 75/15 and change the settings as you suggest which sounds good for solar DC, but this still doesnt solve the issue when charging through the NL5 port on the battery box as this seems to be where there is the throttling.

I did another charge last night where I ran the battery down to 13.2v yesterday, left if overnight on AC charge connected to the battery terminals and it was floating at 13.86V this morning, which is what I expect.

Will do the same exercise again tis evening through the NL5 port to be absolutely thorough, but I kind of know what the outcome will be.

[LandyLove]

Didnt a connection from the port to the battery get damage while doing the battery swop? Dry or broken joint maybe? Have you checked it?

Maybe replace the NL connector (port) with a victron connector. You do get them.

[the_terrible_triplett]

... doesnt solve the issue when charging through the NL5 port on the battery box as this seems to be where there is the throttling.

Did a quick Google, seems the NL5 charger may not be adequate for Lifepo4 ito volts required?
AGM no problem.

Maybe swap the AC charger?

[ekkekan]

Did a quick Google, seems the NL5 charger may not be adequate for Lifepo4 ito volts required?
AGM no problem.

Maybe swap the AC charger?

OP is only using the NL5 input on the box and not a NL5 charger. One would think the NL5 port goes directly to the battery as it is the DC output from the NL5 charger. This mean any suitable external charger should work?

Victron charger/controller is used by OP.

[deanversfeld]

OP is only using the NL5 input on the box and not a NL5 charger. One would think the NL5 port goes directly to the battery as it is the DC output from the NL5 charger. This mean any suitable external charger should work?

Victron charger/controller is used by OP.

Correct yes, I'm only using the input port.

I will open the NL box when I get home later and check all wires are still connected securely etc.

[deanversfeld]

Correct yes, I'm only using the input port.

I will open the NL box when I get home later and check all wires are still connected securely etc.

Here is a picture of charging directly to the terminals and one with using the NL5 input port.

[the_terrible_triplett]

A yes, the Victron 12v/15A charger.

They also have settings to be set, same as the MPPT, for Lifepo4.

Assuming they have been set accordingly, the MPPT and Victron 12v/15A charger, both identical settings, then the "low hanging fruits" have been checked and confirmed.

Thereafter it is another issue, what that is, no idea bar maybe bad connections as has been alluded to?

EDIT:

... 14.2 and float at 13.9v ... charge directly on the the battery terminals, and the Victron AC charger put the battery to 14.1v straight away, and floated at 14v. Now this has me confused as to where the problem lies, ... Could it be the wiring in the NL battery box where there is some kind of voltage drop

If the charger works perfectly directly on the battery poles, and not via the connector, then I would start looking there, yes.

[the_terrible_triplett]

Here is a picture of charging directly to the terminals and one with using the NL5 input port.

A sideline observation, that MPPT inside the box, when in use it is closed I presume (?), the MPPT needs ventilation.

Proof, check the heatsync at the back of the MPPT, it is there for a reason.

[bigboy529]

I don't know that NL box, maybe there's a fuse or other connection behind that NL5 connector which is busy going bad.

As TTT said, rather use the "user defined" setting on both your BlueSmart and SmartSolar chargers to dial in the exact recommended voltages from Blue Nova.

[deanversfeld]

So, update on my investigation and testing, it took me a while but I was able to run the battery down to 13.1v so I could continue testing.

I've opened up the NL box, put the battery on charge through the NL5 import port, sat with my multimeter and checked all positive and negative connections and all show a consistent voltage throughout the system. I can only assume that either on the firmware or circuit board there is some limitation which stops the system from charging to over 13.4v for my LifePO4 battery when connected. I cant proceed further with what I have checked up till now.

I bought my box around 6 years ago, perhaps its been solved since then, but Im going to contact National Luna tomorrow morning and log a query with all my information gathered thus far. Will have to see what they say/recommend. I just cant see that no one else hasnt had this problem with a LifePO4 in the box.
https://www.nationalluna.com/contact-us/

Again, tested the charging directly off the battery terminals, the battery voltage is already at 13.7v and still climbing.....

[GeorgeRGH]

1. On AC via Victron blue smart 12v/15A (via the NL5 charging connection on the NL box)

I've just replaced my NL5 with a Victron 12/15 so my first thought was " How are you doing that?" the NL5 connector and the Victron 12/15 connector are different sizes.

So my assumption is that you have spliced/connected a Victron cable to a NL5 cable. If this is the case, then your problem probably lies with the cable. The NL5 is a 5A charger and the cable is 16AWG, which is only rated for 5A. Anything above that and you are bound to get some voltage drop. The Victron cable is 12AWG and rated for 25A, you might have to modify the NL box and replace the NL5 cable and connector with a Victron.

[GeorgeRGH]

you might have to modify the NL box and replace the NL5 cable and connector with a Victron.

Thinking about it, the wiring from the NL box connector to the battery is probably also only 16AWg so this might have to be replaced as well.

Quick test of the cable would be to feel if the NL section of the cable gets warm, warmer than the Victron section, when charging through the NL connection.

[LGH]

I've had the NL Battery box for a couple years now, and always had a 100ah lead acid in it, with its primary use of running my fridge and camping lights when going camping off/on grid.

As time progressed, I added a Victron 75/15 MPPT to the NL box, and I charged the system via following:
1. On AC via Victron blue smart 12v/15A (via the NL5 charging connection on the NL box)
2. While driving 12v socket in the back of my Amarok into the NL box via red BH
3. Solar while camping through the 75/15.

Happy days...all worked well until my lead acid started giving up the ghost, and I decided to buy the Blue Nova 154ah 2kw lithium for a bit more capacity 2 months ago.

Took the old lead acid out, replaced it with the new BN 154ah, changed the setting on my Victron 12v/15A charger to li-ion, and it should all work fine...right? Now I have to say while charging on AC I have always used the NL5 port on the NL battery box that is connected to my Victron 12v/15A charger, and its worked like a bomb, puts in bulk amps when low, and switches over the float when full. Again...happy days.

What Im finding with the new BN 154ah installed, is that when charging through the NL5 port using the Victron AC charger, it only loads the battery to 13.4v, and then kicks over to float. On the BN website the data sheet indicates it should get to 14.2 and float at 13.9v. Had me stumped until this weekend I stupidly realized I could also charge directly on the the battery terminals, and the Victron AC charger put the battery to 14.1v straight away, and floated at 14v. Now this has me confused as to where the problem lies, as Im almost immediately ruling out the battery, as well as the charger. Could it be the wiring in the NL battery box where there is some kind of voltage drop, but if its a voltage drop, why does the charger stop charging at 13.4v? I've also just come back from a hot Kgalagadi trip where my fridge was almost constantly running at -5 while driving and the loading of the battery via 12v vs the fridge draw was almost identical, which also has me thinking if there is an issue with the box somewhere. With the Victron smart 75/15 I was able to monitor the battery voltage while driving and it never once got over 13.3v, not saying its related but Im out of idea's.

All comments and suggests are welcome as to where to troubleshoot please......

[LGH]

Hi Dean,

I was planning on doing something very similar to you. I'm replacing my Discover battery with the same BN 154Ah battery in my old National Luna battery box. My question to you and the other members is, I have a 10mm2 cable that runs from my primary battery to the back of my Amarok. There it has a red BH connector which normally would have connected to my NL battery box via the red BH input. Now I have been told that I need to install a DC to DC Charger to now charge my battery box because the LiFePO4 battery will draw too much power from my alternator and run the risk of burning out the rectifiers when the battery suddenly drops its' amperage draw. Apparently, it's also better to have a DC to DC Charger in the line so that I can also set the input charge voltage required for the BN 154Ah battery. To this end I was planning on installing a Victron Smart Isolated DC to DC charger.
What is yours and the other members thoughts on this and is it needed.

Many Thanks

[Brent Clark]

The NL5 port according to the NL DC25 box manual can only handle up to 10A. The internal DC controller only allows certain voltages as listed in the manual, so for the Lith and Lith P04 both get BULK at 14.4V and FLOAT at 13.6V.

If your charger is more than 10A, then you need to connect to the Auxillary Input/Output ports.

I guess if you connect the Victron directly to the battery you bypass the DC25 controller and hence the result that you are seeing.

Currently going through this journey to replace the NL5 charger which is not Lithium compatible with the Victron as advised by NL nogal.

Now I am needing the NL5 adaptor as my charger is only 7A.

[Brent Clark]

Hi Dean,

I was planning on doing something very similar to you. I'm replacing my Discover battery with the same BN 154Ah battery in my old National Luna battery box. My question to you and the other members is, I have a 10mm2 cable that runs from my primary battery to the back of my Amarok. There it has a red BH connector which normally would have connected to my NL battery box via the red BH input. Now I have been told that I need to install a DC to DC Charger to now charge my battery box because the LiFePO4 battery will draw too much power from my alternator and run the risk of burning out the rectifiers when the battery suddenly drops its' amperage draw. Apparently, it's also better to have a DC to DC Charger in the line so that I can also set the input charge voltage required for the BN 154Ah battery. To this end I was planning on installing a Victron Smart Isolated DC to DC charger.
What is yours and the other members thoughts on this and is it needed.

Many Thanks

I have the NL DC25 Battery Box and this has a DC/DC charger built in. The source of the charge is from the main battery via a BH connector and it uses a voltage range to switch the charging on and off based on the input voltage from the main battery. This is obviously to protect the main battery from drain.