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Renogy DCC50S for charging DIY LiFePO4 Battery

w28

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I have a Renogy DCC50S combined DC-DC and MPPT charge controller for my camper. I‘m about to purchase the components to make a DIY LiFEPO4 battery pack (first DIY pack for me), but wanted to double check that my charger is adequate for that battery pack.

The cells I’m planning to purchase are 4 x Eve230 Ah with a JBD 150A BMS, which I would use instead of purchasing the more expensive off the shelf SOK 206Ah battery.

The Renogy charger has a built in Li charging profile (shown in screenshot of manual below). Is that suitable/adequate for a DIY pack?

It looks like I could try to program a custom profile, but that would require purchasing the Bluetooth module, which I‘m hoping to avoid if not necessary.

71A09756-BC91-4710-B155-487D5F5687A7.jpeg
 
1) read the manual.
2) Dual mode limits both sources to 25A.
3) Limited to 25Voc (12V panels in parallel only)

That will work fine, but it doesn't float, so it will charge your batteries until they hit 14.4V, and then it will stop. It won't start again until the battery drops to 13.2V. I suspect that if you power cycle the charger, you can get it to restart the boost charge manually.

If you want the solar to charge the battery and then power your loads while keeping the battery charged, you need to set float to 13.6.
 
I just bought one of these last month for my Solar upgrade (previously had PWM being fed by 400 watts of panels)/ LiFePo4 install, I also have the BT-2 bluetooth dongle which allows for setting custom user defined charge profiles, as well as limiting alternator charging in 10A increments, really worth it in my opinion and only adds $25 or so to the cost.
 
Thanks for the replies.

So do DIY LiFePO4 batteries have different charging requirements than off the shelf LiFePO4 batteries?

I looked at the post on recommended charging profile here (https://diysolarforum.com/threads/r...e-for-diy-lifepo4-batteries-sticky-post.5101/) and noticed that the profile is different than the Renogy default (slightly higher absorption voltage and includes float charge as opposed to none).

That post also mentions a “5000 charge cycle“ recommendation for getting your batteries to last longer by setting absorption charge voltage to 14.1V. So if you can get your batteries to last longer by setting absorption voltage lower(at the cost of slower charging rate) is setting it somewhere between 14.5 and 14.1 a good middle ground (the default Renogy is 14.4).

I see there are a number of threads on float charging elsewhere so I’ll read up on those to try and figuring out whether I would need to add that to my charging profile.
 
1) read the manual.
2) Dual mode limits both sources to 25A.
3) Limited to 25Voc (12V panels in parallel only)

That will work fine, but it doesn't float, so it will charge your batteries until they hit 14.4V, and then it will stop. It won't start again until the battery drops to 13.2V. I suspect that if you power cycle the charger, you can get it to restart the boost charge manually.

If you want the solar to charge the battery and then power your loads while keeping the battery charged, you need to set float to 13.6.
It will float if you set it to a custom charging profile using the BT-2 dongle and the bluetooth app
 
Old thread I know, but looking at adding a 12V LiFePOr 105AHr DIY pack from Luyuan for camping trips. Many of the DC-DC chargers appear over marketed and are sold as suitable for all battery types with the appropriate label. Renogy to their credit at least provide info on their profiles and even a user custom profile. To me the Gel cell profile above Bulk to 14.2 and float to 13.8 should allow ongoing charging with loads ( as long as float current is no limited) This seems better than the Lithium profile where discharging to 13.2 needs to happen before return to charging happens. If it's a long small load could be 30-40% discharged, and then you pull up at campsite at nightfall.
This has been mentioned previously by one of our local forum experts as possibly a cheaper foolproof alternative for a DC-DC charger 8-40V to 13.8V 25A for LiFePO4
Would still need a way of protecting main battery.
 
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