Welcome to the Marine Electronics Forums presented by Panbo and SeaBits.

Dc-dc charger not m...
Clear all

Dc-dc charger not maintaining litime batteries

3 Posts
3 Users
Grady Morgan
Active Member
Joined: 3 years ago
Posts: 4
Topic starter  

I recently replaced an AGM house bank woth some litime lifepo4 batteries. I added a renogy 60A DC-DC charger to charge the house bank from the starter battery, off of the alternator, while underway. 

My preexisting cristec AC-DC charger does a good job keeping the batteries topped off while at shore. Underway, the Renogy charger will charge the batteries to 100%. But once they reach 100%, they stop charging and unless I turn the engine off and restart it, house loads will just drain the batteries even though the engine is running. 

Any ideas how to get the DC-DC charger to keep the batteries topped off while underway?



New Member
Joined: 1 month ago
Posts: 1

HY there i can see your post and i must say


  1. Incorrect Charger Settings: Make sure that the DC-DC charger is set to the appropriate charging parameters for lithium-ion batteries. Li-ion batteries require specific voltage and current levels for safe and effective charging.

  2. Charging Algorithm: Li-ion batteries have different charging characteristics compared to traditional lead-acid batteries. Ensure that your DC-DC charger has a charging algorithm suitable for Li-ion batteries, as using the wrong algorithm can damage the batteries.

  3. Battery Health: Check the health of your lithium-ion batteries. If the batteries are old or degraded, they may not hold a charge as effectively. It might be necessary to replace the batteries if they are no longer functioning optimally.

  4. Wiring and Connections: Ensure that the wiring and connections between the DC-DC charger, main battery, and lithium-ion batteries are secure and correctly connected. Loose or faulty connections can lead to charging issues.

Thanks and regards


Roger Gleason
Eminent Member
Joined: 1 year ago
Posts: 11


not sure what your alternator is, but this can happen with a "smart" alternator.  Mercury ( for one)  is now shipping LIN controlled alternators on the V10. 

Good read