back to 3 grab-and-go LiFePO4 battery

580w DC-DC charger:




I recently picked up a refurb LiFePO4 DC-DC charger from Renogy. This one is significantly larger than the
300w LiFePO4 solar controller I already have, but is designed to boost instead of buck. It's rated 40 amps,
though doesn't say if that's source or battery current. At 14.6v absorption voltage, that's about 580 watts.

It's got DIP switches to configure the bulk, absorption, and float voltages to support charging of a variety
of batteries, including AGM, flooded lead acid, lead acid gel cell, LiFePO4, and lithium "deep cycle".

It also includes sense connections for ignition (loss of D+ will cause it to stop charging the battery, even
if source voltage is present and the battery requires charging) as well as a "limit charge" line which will
cut charge current in half. My unit is model RNG-DCDC121240.

Source is rated 8-16 volts, so it definitely can't be used as a solar controller. It's designed to charge a ~12v
battery from another ~12v source of a possibly different chemistry / slightly different voltage, so I can just
use it to charge the lithium battery directly off the lead-acid batteries on Field Day.



Renogy 40 amp DC-DC LiFePO4 charger ($110 at Amazon)



last updated 02/15/2025 at 19:58:11 by make_www_index.command version 2025.02.14.A