Bluetti EB3A Battery Expansion Ideas?

[Christofuse]

Hello Solar Peeps!! Looking for ways I can expand the battery capacity of my Bluetti EB3A power station. Can I add a 50AH lithium battery to it? If so what are some ways to do that and can I charge the lithium battery with solar while using the Bluetti at the same time?

 

[ejfluhr]

IMO, LiFePO4 8s "24v" is the best, as that enables the EB3A to charge at roughly 200W thru the DC input port. You should be able to simultaneously charge the battery via solar with an MPPT controller. You may need to limit charging voltage of the battery to the EB3A max of 28v vs. common value of 28.8v. However, Hobotech on Youtube showed his EB3A ok at 29v in.

I tried charging mine with a 12v battery and it works ok at high states of input battery charge, but once the voltage drops toward 12.0v it loses the ability to charge. As I recall it actually seemed to waste it's own battery trying to charge. So you could not get the full capacity from a 4S LiFePO4 battery. Several Youtubers, like Jasonoid, have demonstrated how adding a 12v->24v converter between the 12v battery and the power station solves that issue and allows for much higher charge rate. However you do pay a conversion penalty doing it that way.

 

[Christofuse]

IMO, LiFePO4 8s "24v" is the best, as that enables the EB3A to charge at roughly 200W thru the DC input port. You should be able to simultaneously charge the battery via solar with an MPPT controller. You may need to limit charging voltage of the battery to the EB3A max of 28v vs. common value of 28.8v. However, Hobotech on Youtube showed his EB3A ok at 29v in.

I tried charging mine with a 12v battery and it works ok at high states of input battery charge, but once the voltage drops toward 12.0v it loses the ability to charge. As I recall it actually seemed to waste it's own battery trying to charge. So you could not get the full capacity from a 4S LiFePO4 battery. Several Youtubers, like Jasonoid, have demonstrates how adding a 12v->24v converter between the 12v battery and the power station solves that issue and allows for much higher charge rate. However you do pay a conversion penalty doing it that way.

THANK YOU for the reply. I might try using a 15A 14AWG 12V Adapter Heavy Duty Cigarette Lighter Plug to connect a 50AH lithium battery to the Bluetti.

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[ejfluhr]

If you are trying to connect the EB3A battery "direct" to the external battery, that won't work. As far as I understand it, the EB3A cigarette lighter plug is "buffered" from the internal battery by a voltage regulator; i.e. it can only output power, not take in power.

The only options for putting power into the EB3A are via the DC input barrel jack, the AC input, or taking it apart to hack in your own connector. Ah, I think the USB-C may also take in power, but I've not used that myself.

 

[Christofuse]

Thank you for your insight.