Balmar 614 vs Li battery BMS cutout

[rgleason]

Somewhat buried on the Battleborn website I found this:
https://battlebornbatteries.com/mari...ems/sailboats/
How do I protect against a high voltage spike back??
(This will occur when the BMS shuts down the battery!!! Why not say so??)

When current is flowing and abruptly stopped or interrupted, there is a potential for a high frequency voltage spike or pulse. Normally this voltage spike is an unwanted feature, as it tends to damage MOSFETs or other solid state switches and relay contacts.
Alternator Protection Device

An alternator protection device, also known as a snuffer, is meant to protect a vehicles alternator if a spike is created. This device gives the spike a route to safely discharge without risk of damaging the alternator.
Issues such as loose wires, blown fuses or a running engine switching off can be some common sources of a voltage spike. The alternator protection device is a cost–effective way to protect a very expensive part of your vehicles charging system.
Sterling Power makes a 12 and 24 volt alternator protection device that can be installed on all vessels utilizing an alternator as a primary charging source.

So Battleborn does address this issue, relies on the Boat's system configuration to address the spike in some practical way.

"Sterling Power makes a 12 and 24 volt alternator protection device that can be installed on all vessels utilizing an alternator as a primary charging source."

The OceanPlanet Wakespeed External Regulator WS500 would be another way to address the problem.

[rgleason]

From the Battle Born website, this is an incorrect statement from the FAQ
https://battlebornbatteries.com/faq/ "Charging and Discharging" at the DoD statement:

Conversely, LiFePO4 (Lithium Iron Phosphate) batteries can be continually discharged to 100% and there is no long-term effect. You can expect to easily get 3000 – 5000 cycles at this depth of discharge.

On this page https://battlebornbatteries.com/mari...ems/sailboats/
At the bottom, "Why is my battery registering 0-5 volts?"

If your battery registers between 0 to 5 volts this means that it’s in low voltage disconnect mode. This happens if the battery has been drained of capacity and is protecting itself from further discharge.
At this point you will need to apply a direct 12 V source such as the alternator via the starter battery or by connecting it to your starter battery with jumper cables until you see the voltage reaches 10-10.5 V.
Some inverter chargers will also bring the batteries out of low voltage disconnect.

The first statement is totally misleading, because the Battle Born Batteries are protected by a BMS from deep discharge which will cause any LiFePo4 battery to fail! Battle Born should rewrite the first statement.

[OceanPlanet]

Originally Posted by rgleason

Here is a statement from a Battleborn installation:
https://www.solar-electric.com/lib/wind-sun/Battleborn_BB10012_specifications.pdf

This battery has + and - connections, no indicators and no means of communicating. The BMS is configured to protect the battery without much concern about the entire system configuration and charging devices.

However Battleborn seems to think that their battery is fine in FLA configured systems, provided the charging devices are properly set!

Yet OceanPlanet recommends the Wakespeed AP500 which is a sophisticated charger for charging Lithionics exactly why do we have these differences in approach, and what are the risks with the Battleborn approach? Are they significant?

IMHO, different horses for different courses. With lower current charging sources, and/or smaller alternators, the Battleborn may work fine. A Sterling APD might save the alternator in a cutoff. However...will it save any other sensitive electronics that may still be connected to the alternator when the Battleborns cut themselves off? Would love to hear from volunteers willing to open-circuit their alternator with an APD installed, with all their instruments/etc. up & running to see what happens...;-) Good luck and keep us posted on the results.

The Li3/Wakespeed config is definitely more expensive and complicated. Perhaps mostly applicable to high-output alternators and powerful charging systems. However the extra protection and the graduated charging control is a good option for those wanting a smarter and safer system.

[rgleason]

The Li3/Wakespeed AP500 or simpler WS500 config is more expensive and complicated. Mostly applicable to high-output alternators and powerful charging systems. However the extra protection and the graduated charging control is a good option for those wanting a smarter and safer system.

Do the Li3 Batteries communicate with the Wakespeed via Canbus or some other bus to disconnect the Alterator Filed? Click on "Learn how the BMS works"

FCC (Field Circuit Control) Alternator/ charge source protection: All OPE-Li3 BMS units come with a simple alternator disconnect circuit. The BMS will automatically turn off the alternator or other sensitive charge source before a high voltage cutoff, thus protecting your alternator(s)/charge sources in an HVC situation. This is a simpler and more robust solution than having the BMS communicate with the alternator through the CANbus network.

Note the Lithionic Batteries with an internal BMS doe not have an alternator disconnect circuit.

[OceanPlanet]

Do the Li3 Batteries communicate with the Wakespeed via Canbus or some other bus to disconnect the Alterator Filed?

Yes. The Li3 BMS and the Wakespeed speak the same CANbus (RV-C). And in addition to the CAN we usually use the FCC to control a relay that can cut the power to the Wakespeed. It's a bit redundant, but gives multiple layers of protection.

[rgleason]

Witsgall wrote:

There are two avenues for setting up the MC-614 for use with LFP batteries. If you have an older MC-614 without the built-in LFP profile, then go to our website and grab the service bulletin for setting it up to use LFP batteries: https://balmar.net/service-bulletins/

It is well worthwhile reading this bulletin, particularly the "Additional Notes".

1. ...Battery Management System (BMS) that may disconnect the battery from the alternator when charging is complete. This is doubly true if the battery can be disconnected during high current charging, causing a load dump. The load dump can easily cause a high voltage spike which will destroy (the alternator and electronics) ... The Alternator must be shut down before disconnecting the battery. The only safe way to shut down the alternators is turn off the regulator. The preferred method is to disconnect the regulator's ignition wire...

2. Applying too much charge current to a LFP battery will, at the very least, permanently damage the battery's capacity. It is CRITICAL to ensure that the alternator is not capable of exceeding the maximum continuous charge current rating of your battery (or batteries).... you may use the Belt Manager feature on the MC-614 / MC-612 DUAL to lower the maximum field drive output, and thereby lower the maximum alternator output current.

3. It is strongly recommended that an alternator temperature sensor (MC-TS-A) be used when charging LFP batteries. ....high charge acceptance rate of LFP batteries, the alternator will be driven to full output for almost all of the charge cycle...cause alternator overheating which will significantly.... When equipped with the MC-TS-A temperature sensor, the MC-614 or MC-612-DUAL will help you protect your investment by performing active alternator temperature control. This is accomplished by scaling back the field voltage to the alternator when over the "AL1" temperature threshold.Also use the Belt Manager feature ...to reduce maximum output until a tolerable alternator temperature is maintained under all conditions.

NOTE: Others have said "Not to use the battery temp sensor" This is wrong.

4. .. LFP battery... specify minimum and maximum charging temperatures to be from freezing (32°F, 0°C) to around 111°F (44°C). When equipped with a MC-TS-B the MC-614 or MC-612-DUAL can disable charging if the battery temperature exceeds the "B1L" temperature threshold and re-enable charging when the temperature drops below the threshold. This feature is meant to supplement, not replace, your BMS's temperature protection features. "B1L" should be adjusted to be slightly less than BMS's temperature threshold).

[rgleason]

Originally Posted by OceanPlanet

Do the Li3 Batteries communicate with the Wakespeed via Canbus or some other bus to disconnect the Alterator Filed?

Yes. The Li3 BMS and the Wakespeed speak the same CANbus (RV-C). And in addition to the CAN we usually use the FCC to control a relay that can cut the power to the Wakespeed. It's a bit redundant, but gives multiple layers of protection.

In my opinion this is the way it should be done!

The Lithionics Li3 with External BMS does this,
but the smaller Lithionics Batteries with an Internal BMS do not.

How is the alternator field cut off done with the smaller Lithionics batteries?

[OceanPlanet]

Originally Posted by rgleason

In my opinion this is the way it should be done!

The Lithionics Li3 with External BMS does this,
but the smaller Lithionics Batteries with an Internal BMS do not.

How is the alternator field cut off done with the smaller Lithionics batteries?

Li3 isn't doing much in the way of small batteries anymore. Some are shown on the website however they aren't made except for volume orders. However, the new GTX12V315A-E2107-CS200 (315Ah x 12.8V) have an internal BMS with both CANbus and FCC. For bigger systems we prefer the external dual channel BMS, however for smaller & mid-sized apps the 315Ah @ 68lbs with the BMS controls is a nice package. We're about to order 10 of these for stock.

[rgleason]

Yes, I saw that series GTX12V315A-E2107-CS200

Length 20.3"
Width 6.4"
Height 10.0"
Approx. 68lbs (30.8kg)

Unfortunately it is more amphr than I think I need (240-200ah) and it is bigger than I can fit. Weight would likely be ok for removal in winter.

[Karanga]

Isn't it amazing to see the wide range in comments, opinions, facts, contradictions, theories, hardware recommendations and brand differences when Li batteries are discussed?!
And from experts and newbies alike!!
It's not surprising that dumbos like me can't maintain much of an understanding...
Maybe this is part of the price for early adoption (in addition to the actual prices, which continue to drop dramatically).
But the input from all the contributors is valuable and appreciated.

Tim

[rgleason]

@Karanga

I have have followed this all the way through and understand it, the facts are pretty clear and the goals are absolutely clear. See and read the Battle Born documentation, the Balmar documentation, and the OceanPlanet Lithionics documentation. When you dig into it these manufactures do not conflict regarding the best and safest installation!

[Karanga]

Thank you
I guess what threw me was the recommendation (instruction?) to disconnect /disable the battery temperature sensor.
That and the threatened potential risk of "killing" Li batteries by charging at what I thought were not significantly diverse charging rates.
My older 614 regulator seems to go through a reasonable charging profile of bulk-absorption-float-shut off. However, due to being confused/fearful, I now often run the motor with the alternator and regulator switched off, leaving charging to happen via genset and solar.
Tim

[rgleason]

1. The BMS may shutdown the LFP batteries for a number of reasons.
2. The alternator and electronics will suffer from a huge spike and fail if protection isn't provided.
3. The protection can be provided in any number of ways, best ways listed first.

• Configuration: Dual bus (charge/discharge) BMS signal to shutdown Alt prior to shutdown. Lithionics.
• Configuration: Hybrid LA/LFP Frans' take on a hybrid LA/LiFePO4 system
• Configuration: Alt charge to AGM Bank use DC/CD 12/12 charger to LFP Bank. (Sterlinig or Orion-Tr Smart DC-DC charger, see diagram) Will these really protect the alt and electronics? Does not offer faster high charging amps.
• Sterling Power Alternator Protection Device that can be installed on all vessels utilizing an alternator as a primary charging source. (Much like Zap Stop) Listed by Battle Born.
• Protect Alternator: Zap Stop (would only protect the Alt, but would it protect at high charging amp. Does not protect equipment from spikes. This should only be used as a backup! (Does not protect DC Panel)
• There may be some other configurations or devices which might help.
• Victron BMS 12/200

Careful -Alternator Charging Lithium

[rgleason]

Karanga wrote:

"...to disconnect /disable the battery temperature sensor."

I agree about this confusion. I think that Balmar's response is most accurate, see #4 below. We should continue to use the Battery Sensor, but set the "B1L" in your Balmar 614 program as they state.

I think some of the confusion comes from setting "Temperature Compensation". LiFePo4 requires "0" temperature compensation so the alternator output is not changes with temperature (LiFePo4 batteries have very little resistance). You should still use the battery temperature sensor "B1L"

I suggest you read MainSail's Marine How to about Balmar Regulators if you have not already, it is step by step and very helpful. You have a great regulator there and really will need to use it when you get those Battleborn Batteries!

https://marinehowto.com/programming-a-balmar-voltage-regulator/

https://marinehowto.com/balmar-mc-614-alternator-service-disconnect-switch/

[Karanga]

Thank you for this nice summary.
I now have a bit more confidence in my system, with the semi Li/LA hybrid setup

Originally Posted by rgleason

1. The BMS may shutdown the LFP batteries for a number of reasons.
2. The alternator and electronics will suffer from a huge spike and fail if protection isn't provided.
3. The protection can be provided in any number of ways, best ways listed first.

• Configuration: Dual bus (charge/discharge) BMS signal to shutdown Alt prior to shutdown. Lithionics.
• Configuration: Hybrid LA/LFP Frans' take on a hybrid LA/LiFePO4 system
• Configuration: Alt charge to AGM Bank use DC/CD 12/12 charger to LFP Bank. (Sterlinig or Orion-Tr Smart DC-DC charger, see diagram) Will these really protect the alt and electronics? Does not offer faster high charging amps.
• Sterling Power Alternator Protection Device that can be installed on all vessels utilizing an alternator as a primary charging source. (Much like Zap Stop) Listed by Battle Born.
• Protect Alternator: Zap Stop (would only protect the Alt, but would it protect at high charging amp. Does not protect equipment from spikes. This should only be used as a backup! (Does not protect DC Panel)
• There may be some other configurations or devices which might help.
• Victron BMS 12/200

Careful -Alternator Charging Lithium