23.2 Voc Solar Panel vs 24v Battery

safaenetsafaenet Registered Users Posts: 1
Hi, I'm new to solar and have a question in my head: Can we use a 23.2 Voc Solar panel to charge a 24v Battery (2x12v in seris) using a 10Amp 12-24v PWM charge controller ?
Here are the specs:
Solar Panel:
Model: Yingli YL80c-18b Mono
Rated Power: 80w
Rated Voltage: 19.1v
Rated Current: 4.19A
Voc: 23.2v
Isc: 4.42A
Max system voltage: 50v

Batteris: 2x12v 4.5Ah conventional battery
Charge controller: LandStar LS1024EU which supports 12-24v


  • EstragonEstragon Registered Users Posts: 4,451 ✭✭✭✭✭
    edited July 2018 #2
    You could put 2 panels in series for ~38Vmp and ~4a assuming the controller is ok with Voc. If you're in a cold climate, Voc could get close to the 50v limit of the panels..

    One panel wouldn't work for 24v nominal bank (needs ~28ish volts for charging).
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • BB.BB. Super Moderators, Administrators Posts: 30,037 admin
    You need Vmp-std ~35-40 volts to "reliably/quickly" recharge a 24 lead acid battery in most conditions.

    Voc (voltage open circuit) is the panel voltage when there is no current flowing--Not useful for charging/running DC loads.

    Two of your panels in series would be the normal setup for a PWM controller charging a 24 volt  battery bank (Vmp-array~38.2 volts in standard test conditions).

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • PhotowhitPhotowhit Solar Expert Posts: 5,101 ✭✭✭✭
    The panel is a 12 volt nominal panel and you could put the batteries in parallel and charge it at 12 volts.

    The batteries are very small at "...12v 4.5Ah conventional battery..."
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
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