Lithium battery as starter assist

pianotuna wrote:
Why? The battery management systems on Li batteries limit the output to about 100 amps (some are more some are less).

Battleborn will allow a 200a surge for 30 seconds.

Yes. However 100 Ah might be light for general use and for the boost start. Worst case it will not work and you will have to do something else to get started.

ramsaymike wrote:
I am considering changing out the house batteries with a single 100 ah lithium. In certain conditions I need to use the battery combiner dash switch to start the engine. Would this still be possible with the lithium battery? Thanks.

The short answer is NO, unless there is a massive Li battery bank.

Why? The battery management systems on Li batteries limit the output to about 100 amps (some are more some are less). The starter draws hundreds of amps.

You could do what you want with an SiO2 battery, which are able to do a 4C rate continuously, and 9 C for 5 seconds (400 amps from a 100 amp-hour battery)

Then you'll need an Li battery that can deliver 2c. Not all can.

Starter batteries (2) are conventional lead acid. I generally see max current is 2c so I think 200 amps 3-5 seconds for the li battery I am looking at. I don't know if the BMS would protect the protect the battery or I would risk damage.

Original house batteries are deep cycle lead acid.

What are the existing house batteries? Starters can take hundreds of amps.