Charge Battery From Generator Unregulated DC

[dmholmes]

Can I charge a LiFePO from an unregulated DC outlet in a gas generator?

 

[gnubie]

Only with something to intervene and control the voltage / current. Left to its own devices the lifepo4 will be able to draw enough current to cause problems or break the DC output of the generator; or itself; or both.

 

[dmholmes]

Only with something to intervene and control the voltage / current. Left to its own devices the lifepo4 will be able to draw enough current to cause problems or break the DC output of the generator; or itself; or both.

Some kind of DC to DC charger/controller?

 

[gnubie]

Yes. What's the typical voltage range from your generator's DC output and your nominal battery voltage?

 

[GXMnow]

You should use a charge controller of some kind to limit the maximum current and the maximum voltage. All lithium type cells should be charged in a CC CV mode. Constant Current (CC) "bulk charge" until the maximum voltage is reached, then hold Constant Voltage (CV) with the current tapering off to get full capacity in the cells, also called "absorption charge" stage. Absorb charge is not required, but will push another 10% of energy into the cells. LiFePo4 cells should typically not charge faster than 1C or current equal to the amp hour rating. Some can take a bit more, but check the data sheets. And the Absorption voltage is typically 3.65 volts per cell. So a 12 volt pack is normally 4 cells in series which comes out to 14.6 volts.

 

[Forbisher]

Can I charge a LiFePO from an unregulated DC outlet in a gas generator?

Why?
Why not just plug in a LFP battery charger?
What size and type of LFP?

 

[theoldwizard1]

The 12VDC output on portable generators is its "life blood" ! All of the "smarts" inside use that power. If it is compromised you are SOL !