The Renogy Wanderer states that it is optimized for 10A, 12V/24V batteries. What would happen if it was connected to a battery pack containing one 3.6V 18650 battery such as this?

  • Frater MusEnglish
    2•6 months ago

    Nominal 12v panel + nominal 12v battery is good, and the Wanderer will charge LiFePO4 with a canned profile IIRC.

    Here’s the next hurdle: I’d expect a 10w panel on PWM to max at ~7w under excellent conditions; we could estimate this more accurately better if we knew the panel specs. And the controller will require a certain amount of power to run its own innards. The Wanderer 10A specs say Self-consumption <10mA but this may be with the panel[s] disconnected, or when the panels are connected but there is no PV input. Or it may really be <10mA in all cases; not much electronics inside a PWM compared to MPPT. If you do it please report back with what you find.

    These kinds of challenges are common in very small (experimental, learning) solar setups; when the numbers get larger this kind of challenge largely gets lost in the noise of bigger numbers.

      • Frater MusEnglish
        2•6 months ago

        Isc 0.61A

        We can ballpark maximal/theoretical harvest by multiplying the bank voltage (Vbatt) by the panel’s short circuit current (Isc).

        • Vbatt 10.0v - ~0% SoC = ≤6.1w (Isc 0.61A x Vbatt 10.0v)
        • Vbatt 13.0v - ~50% SoC = ≤7.93w
        • Vbatt 14.0v - 100% SoC = ≤8.54w

        Real world conditions and esoteric concepts like I/V curve fill factor will conspire to depress observed current (A) and therefore observed harvest (W). The quick math to above is just to illustrate how the bank voltage tail wags the PWM dog.

        Keep us in the loop about how the project turns out. :-)