Hi! I think I have an easy one that I just want to confirm. Current setup is 2x Renogy 100 watt panels to a SmartSolar MPPT 75/15 to 2x 100ah AGM batteries in parallel. The AGMs are getting up there in age (came with the camper) and I’ll be replacing them in the next couple months. Can I plug and play 2x lifepo batteries with that setup? 12v system. Using a Smart BMV712 to monitor.
Thanks!
Vince
Yeah, no problem. Just connect to the MPPT, go to Settings > Battery and choose the LiFePO4 preset. You will need to change the capacity setting on the BMV too.
As far as the presets, is that pretty straightforward?
Trying to decide whether to replace before a month long trip starting in late June or wait until we get back. There isn’t an issue at the moment, just being a little paranoid. It wouldn’t be the end of the world to replace during if the need arises. The batteries are around four years old.
Yes @Vinman capacity is consistent across chemistries in that sense. ie if rated for 100ah AGM and swapping for 100ah lifepo4 (assuming no voltage changes) then that number wont change in settings.
Personally i find the presets in victron systems a little high for charging lifepo4, so I use custom settings and lower mine but I'm using a DIY built lifepo4 so if you're not that bothered then it should be as easy as Paul mentions just changing the setting to preset.
Also disable temperature compensation.
You should check discharge floor in the 712. For AGM it's usually about 50%, with LiFePO4 it should allow 80% use before alarm is set off, I can't remember if it means that you enter 20 or 80%, so check the manual.
On the charge parameters, always better to go with the battery maker's recommendations. The Victron defaults will work, but may not be optimal, as @matt1309 said.
