Battle Born Performance & Charging

[ROBERT CROSS]

Posting results, advise & recommendations.

Basic Kiss system here, 2 100ah with new cables, Boondocker adjusted to 14.4v and a 700 series monitor.

First thing I noticed was a low voltage warning at 11.94v
at 47% SOC...Normal?
I thought it would be it be closer to 20%.

Bob
🇺🇸

[uncle_bob]

Hi

Yes indeed a bit unexpected.

With "tail current" set to 4% (at least as I understand it) the Victron will decide the battery is at 100% charge when the current drops below 4% of 200A = 8A. That may or may not be what you want it to do. I have my tail current set a bit lower than that and I have 400AH of batteries. I also have "charged voltage" set a bit higher, but don't remember off the top of my head if that has any impact on anything at all.

One question - last screen shot on a different thread was playing with the furnace around 38F or so. Are the batteries cold-ish right now?

I'd suggest calling Nevada but a call I made earlier in the day got a totally nonsense reply to my question. I will admit that it probably was lunch time when I called. I put it all in an email via their web site, we'll see if I get a reply any time soon ....... yes I do believe that's called hijacking somebody else's thread .....

Bob

[ROBERT CROSS]

Originally Posted by uncle_bob

Hi

Yes indeed a bit unexpected.

With "tail current" set to 4% (at least as I understand it) the Victron will decide the battery is at 100% charge when the current drops below 4% of 200A = 8A. That may or may not be what you want it to do. I have my tail current set a bit lower than that and I have 400AH of batteries. I also have "charged voltage" set a bit higher, but don't remember off the top of my head if that has any impact on anything at all.

One question - last screen shot on a different thread was playing with the furnace around 38F or so. Are the batteries cold-ish right now?

I'd suggest calling Nevada but a call I made earlier in the day got a totally nonsense reply to my question. I will admit that it probably was lunch time when I called. I put it all in an email via their web site, we'll see if I get a reply any time soon ....... yes I do believe that's called hijacking somebody else's thread .....

Bob

Yes... this was taken At the end of that test. The rest was pretty much as expected.

SOC, voltage and consumed AH matched pretty well half way thru the test.

Bob
🇺🇸

[uncle_bob]

Hi

I wonder if one battery is MIA? The numbers all would make sense for a single battery.

Bob

[ROBERT CROSS]

I wondered the same thing this morning as I fried my brain on the charger...called BB, no call back yet.

I pulled the pos on each battery and did a screen shot...🧐
Numbers match exactly, unusual? 😳

Both batts were within .4v out of the box and I charged them separately before install and again when I sync'd them.

I'm in the middle of another draw test now, 6.5a constant, (no furnace).

Bob
🇺🇸

[uncle_bob]

Hi

It may just be a function of my lack of imagination, but the only ways I can think of for the battery to be MIA are for a wire to be loose or for the battery to be defective. A multimeter check post to post should tell you if a wire is the issue. I would *guess* that pulling a wire or two would tell you if a battery has failed completely.

As part of my ongoing hijack effort - I've heard nothing at all from BB on my request for info. Maybe they are all at some big RV show in Tahiti ...

Bob

[ROBERT CROSS]

I doubled down and sent them an email with the relevant screenshots...made sure they understood that they had a pretty good rep on the Forums and that I was the VP of unappreciated reviews.
Wait & see, I've heard they have been pretty good with CS...we'll see. 😳

Bob
🇺🇸

[uncle_bob]

Hi

I got my email back. Based on what they said in that email, anything below 24F is bad for the batteries (in terms of storage). They are still saying that -4F is the "BMS stops discharge" point so I am *very* confused. I'm interested in seeing what they come up with in your case. Either they have had a significant change in thinking on their batteries or somebody there is a bit mixed up ....

Bob

[ROBERT CROSS]

I got my call-back this morning.

It was my own dumb fault...I had set the new Boondocker to 14.4v but neglected to set it to "fixed output".
The BB's were never getting enough to reach 100% real world. 😳

Bob
🇺🇸

[AirMiles]

Thanks Bob for posting your results and learning pains. I like the real world experience threads rather than rehashing the glossy marketing brochures over and over. I hope you will post more on your future BB lithium experience.

[uncle_bob]

Hi

As posted elsewhere, but repeated here for completeness:

When I got my "fixed output Lithium" charger, it also came with the magic switch set to the variable (lead acid) position. That created a bit of confusion here as well.

Running at 13.2V (assuming that was what it was), the BB's will get to roughly 70% charge. If it is a bit above this (like by a tenth of a volt) the charge level will be a bit higher. Equally, a tenth of a volt less and it will be much lower.

The odd thing is that most of these chargers cycle up to "full output" mode when plugged in. That *should* have taken the batteries up to full charge. Even getting them to the 13.6V level should have them above 90% charge.

If you have solar, the same sort of thing applies to a lot of chargers. The sun comes up in the morning and they decide to go through a full cycle. Up they go to 14.x volts and then back down again. Tomorrow is a whole new day .....

Lots of fun !!

Bob

[ROBERT CROSS]

I re-set the Boondocker and the charged voltage went right where it should be...wonder of wonders, do it rite the first time...😂

Bob
🇺🇸

[uncle_bob]

Originally Posted by ROBERT CROSS

I re-set the Boondocker and the charged voltage went right where it should be...wonder of wonders, do it rite the first time...��

Bob
����

Hi

So when is the next discharge test?

... trust but verify ....

===

Back to my hijack - just got a call from BB and indeed there had been a disconnect between the question I was asking and the question they were answering. Bottom line: storage at 0F is still ok as long as you disconnect the loads. I can calm down again ....

Bob

[ROBERT CROSS]

Originally Posted by uncle_bob

Hi

So when is the next discharge test?

... trust but verify ....

===

Back to my hijack - just got a call from BB and indeed there had been a disconnect between the question I was asking and the question they were answering. Bottom line: storage at 0F is still ok as long as you disconnect the loads. I can calm down again ....

Bob

As we speak...Started yesterday. Looks much better, what think 'ye?

Bob
🇺🇸

[SCOTTinNJ]

I have a boondocker charger and a victron solar controller. For the life of me I couldn't get the boondocker ti charge my battle borns correctly. Seemed to be set too high so they stay at 14.4 or too low where it shuts down. I think it's because of voltage drop between the charger mis trailer and my batteries up front. Maybe a 15-20' run with whatever wire airstream used.

Anyway I settled in on leaving the boondocker low and manually turning it on when i need it (it automatically starts at 14.4). Otherwise i let solar do the heavy lifting day to day.

Maybe that's an option for someone who cant dial in a charger?

[ROBERT CROSS]

^
?
Is it the adjustable BD1260L.

It will stay at a 'fixed' voltage,(you set it), if set in the mode for lithiums. That was my problem I had the lithium voltage set properly at 14.4v but in the stage mode not fixed. It went into float and never finished the lithium charge cycle.

Our BD will charge to 14.4 but settle to 14.2 after a short rest. I synchronized 14.2 @ 100%

Bob
🇺🇸

[SCOTTinNJ]

It's the bd1260hw, so the hardwire version. I can set it to constant voltage or variable.

If I set it to read 14.4 at the charger my meter might read 13.9 or so at the batteries. There seems like a lot of loss on the way. So I would need to set it at 14.9 to get 14.4 at the batteries (my numbers might not be right but it's a sizable spread, at least 0.3v).

I dont like setting it so high so I keep it at 14.4 variable. But that sets the float too low to kick on because the batteries dont usually go that low. Float at the charger is 13.2 but only 12.7 or 12.8 at the batteries.

I used this to set it up.

https://battlebornbatteries.com/powe...po4-batteries/

12.8v is around 20% battery life. I never let them get down that far but instead (taking solar out of the equation) I cycle the converter on and off to force it into 14.4 mode. Even then it only charges for 20 min at large amps (20-25 even though rated higher) before dropping down to 3-4 amps. I can leave it there or cycle again to charge quicker.

All of this is a bit moot because I have 400w of victron solar that I set at 14.4 and 13.6. The controller is a few feet from the batteries and works perfectly.

[ROBERT CROSS]

Are you measuring at the batts with them connected?
they must be out of the loop when setting fixed charge voltage, 14.4V is our max chg rate, the battery will rest at around .5v lower when off charge.

The set-up you have referenced in your link goes against what BB CS told me to do with our Boondocker converter.
The reason I wasn't getting a full charge was because the converter was switching to float.
Going back to 3 stage charging defeats the purpose of setting the fixed voltage... and using the BB's BMS.
Have you called them? Give them a call ask for Dennis.

><><><><><>><><><><><><><><><><><><><><><><><><><> <><>

Test results after setting converter to 14.42v fixed voltage.

50% SOC pretty well matches the 103AH used, only outlier is the time remaining value?
12.93v is a bit more that I expected after 26hrs.

I'm letting this run to 40% to ck voltage at that %.




Bob
🇺🇸

[uncle_bob]

Hi

The "stock" way to run the simple "lithium" chargers is as a fixed output voltage. Fixed is fixed, it does not change at the converter output terminals. You can / do / will get some drop in the wires with lots of current running. As the batteries approach "full" the current will drop back ( = the battery is no longer charging heavily). As the current drops, the voltage drop on the wiring also drops. Net result is that a converter set to 14.6V will put 14.6V on the batteries.

In theory, there are a lot of other ways you *could* do things. With a networked controller, you might sense voltage at the battery with another device. With a different converter design, you could run long sense wires over to the battery and adjust the output accordingly. Lots of fun to think about, but that's not the way they actually work.

If your converter is varying it's output voltage then the magic fixed / multi switch is in the wrong position. It's not at all unusual for them to arrive with a "lithium" sticker on them ( = switch should be in the fixed position) and have that switch in the wrong position ....

Lots of fun !!

Indeed, with a programable converter charger, you can set it to charge up at 14.x V and then drop back to 13.6 or 13.7V. That seems to be the "best" way to do things.

Bob

[ROBERT CROSS]

Took the BB's down to 40%, quite happy with the results.
Start>>Finish>>Rest👍

Bob
🇺🇸