Can I Use an Echo Charge With Different Battery Chemistries?

Question:

I bought a used Najad 380 one year ago and I’m planning to prepare it for a long voyage. I’ve been following your videos for some time now – they’re great, thanks! I wish I had someone as experience as PYS nearby!

In one of your videos you’ve mentioned the Xantrex Echo Charger as a possible solution to use on a PV charging solution so it can charge two battery banks at the same time (with single output solar controllers), specially when they have different capacities. The manufacturer says that “both battery banks must be the same DC voltage and battery type”.  My starter battery is a Exide ER 350 Dual, and my house bank is a 3x Exide EP1200 Dual AGM.

Can I use the Echo Charger in this situation? Or the battery type must be exactly the same? - Rui

Answer:

A Xantrex echo charge is just a directional battery combiner. It effectively puts both of your battery banks in parallel whenever there is a charging voltage. If you have different battery chemistries, you are better off with a DC to DC charging converter instead of the Xantrex echo-charge.