Which reserve battery do you use with LiFePo4?

[ronstory]

senormechanico--

Cool, sound similar to what I will have. What BMS did you pick?

[ronstory]

John--

The Sterling DC-DC converter is a cool idea. The manual is bit vauge... any ideas if you can turn off float?

[ronstory]

Hellosailor--

Yes, I've had a LFP battery in my motorcycle for 5 years, they are a completely different learning curve from FLA. Also, got to work in portable PC industry and some of the earlier forms of Lithium were rather "finicky".

[Q Xopa]

Originally Posted by ronstory

John--

The Sterling DC-DC converter is a cool idea. The manual is bit vauge... any ideas if you can turn off float?

What most people do is just set 'float' a bit lower, 02v maybe, than the bulk setting. You can do that with Sterling DCDCs

[john61ct]

No DCDC source has zero Float afaik, very few sources of any type do.

A switch or relay could just cut off its input or just isolate the bank, depending on your design.

[Q Xopa]

Originally Posted by john61ct

No DCDC source has zero Float afaik, very few sources of any type do.

A switch or relay could just cut off its input or just isolate the bank, depending on your design.

If you look at https://sterling-power.com/collectio...rip-proof-ip21

Features 11) 4 Stage charging.

[john61ct]

Sorry do not see what you're trying to say.

They wanted to be able to Just Stop, disable dropping to Float

[Q Xopa]

Originally Posted by john61ct

Sorry do not see what you're trying to say.

They wanted to be able to Just Stop, disable dropping to Float

If you scroll down the link page they refer to '4 Stage charging', ie Bulk, Absorb, Float etc.

Most people set Bulk and Absorb to a higher V than Float. This will mean that the Charging is 'tricked' to Stop when the Absorb Voltage is hit because it is higher than the Float setting Voltage.

[john61ct]

Bulk / Absorb being higher than Float is the norm.

I think maybe you're trying to talk about the "trick" of setting Float higher, matching Absorb, for chargers that can't adjust AHT long enough, drop to Float prematurely?

Again, the scenarion here is the opposite; many chemistries are best off with "Just Stop" once Full, on the few sources that accommodate such, they have a Float = Off option, the charger just shuts down.

[Q Xopa]

Originally Posted by john61ct

Bulk / Absorb being higher than Float is the norm.

I think maybe you're trying to talk about the "trick" of setting Float higher, matching Absorb, for chargers that can't adjust AHT long enough, drop to Float prematurely?

Again, the scenarion here is the opposite; many chemistries are best off with "Just Stop" once Full, on the few sources that accommodate such, they have a Float = Off option, the charger just shuts down.

Ah I think Im starting to work out your short hand codes. AHT = Amp Hours Trailing right?

Somebody still has that? Last I heard Victron had it but dont now.

[john61ct]

Absorb Hold Time

How most adjustable charge sources determine charging stop point (drop to Float)

Eggtimer not as good as a sophisticated algorithm like Victron's, but usually can extens.

Best is endAmps, based on measuring trailing acceptance directly

[Q Xopa]

Originally Posted by john61ct

Absorb Hold Time

How most adjustable charge sources determine charging stop point (drop to Float)

Eggtimer not as good as a sophisticated algorithm like Victron's, but usually can extens.

Best is endAmps, based on measuring trailing acceptance directly

Ah my bad, just when I thought I was starting to pick up on some of your short hand.

[Q Xopa]

Originally Posted by john61ct

Absorb Hold Time

How most adjustable charge sources determine charging stop point (drop to Float)

Eggtimer not as good as a sophisticated algorithm like Victron's, but usually can extens.

Best is endAmps, based on measuring trailing acceptance directly

Ok, sounds good- endAmps. Any ideas which chargers can do it?

[john61ct]

shore or solar?

[ronstory]

I'm gonna say 'shore' ... just to see how this discussion ends.

Sorry, work has interfered with forum time, but catching back up.