Lithium cranking batteries

[baitable]

[QUOTE=NAGG;1694429]

I guess it depends on the battery chosen - The BMS & how it is configured

DCDC chargers are recommended when you have "smart alternators" for exactly that reason

An outboard with a dumb alternator is less of a concern if your Lithium battery is designed for the application (like my Lithiumax) ...... most are not though.

In my Canopy I run an Enerdrive system - because the Navara has a smart alternator.

Chris

Dc2dc chargers are recommended because lithiums require a specific profile to be kept in peak performance which a normal alternator cannot provide. The lithiumax bms will still shut off in the event of an error to protect the battery in the event of extreme low or excessive volts and stop charge going into the battery- it will not stop a voltage spike running from the up hill side of the battery mate- I too have spoken to lithumax and derived my own opinion. At the end of the day it’s your boat and your choice- I’m just stating the limitations of the system.

[NAGG]

[QUOTE=baitable;1694434]

Dc2dc chargers are recommended because lithiums require a specific profile to be kept in peak performance which a normal alternator cannot provide. The lithiumax bms will still shut off in the event of an error to protect the battery in the event of extreme low or excessive volts and stop charge going into the battery- it will not stop a voltage spike running from the up hill side of the battery mate- I too have spoken to lithumax and derived my own opinion. At the end of the day it’s your boat and your choice- I’m just stating the limitations of the system.

Don't worry - I'm hearing you & agree

Have you found a DCDC charger that can withstand salt water exposure ? ...... I know my Enerdrive 40amp wouldn't be a candidate .

Chris

[Lovey80]

Just to bring this back up.

I’ve been researching my options in this space for a little experiment I have planned using 40Ah Yinglong Lithium Titanate oxide batteries (for a cranking battery). Because they have a very high charge limit voltage in a 6S configuration of 17.4v. Coupled with the fact they have very high charge/discharge qualities, I was thinking that I could get away with not using a BMS all together, or even if I did, the BMS would never disconnect for over voltage protection running off the alternator/regulator of the outboard.

This sat really uneasy with me and would partially negate the experiment if I couldn’t monitor exactly what was going on through a battery management system.

Today I found his little gizmo that should put me at ease about frying my alternator if there is an issue and the BMS (or another scenario) produces an open circuit situation while the engine is running. This should also be applicable for anyone wanting to use LifePo4 batteries as cranking batteries.

https://sterling-power.com/products/...tection-device

or

https://www.outbackmarine.com.au/bal...module-12-volt

would be great to get any of our resident leccy experts to weigh in on this.