gregoryjward wrote:GeekEV wrote:gregoryjward wrote:I've been attempting to measure whether the solar panels are charging the battery or not. I have full sun on them around noon and am monitoring the 12-volt battery at around 12.62 volts on my digital voltmeter. Covering the panels doesn't change the voltage at all, even after waiting several minutes. Uncovering the panels again likewise does nothing. There should be at least a small change in voltage if the panel is charging the battery.
In the service manual it looks like the solar panel is more-or-less directly wired to the 12v battery. As a result, you're probably measuring "backflow" from the actual 12v battery. The proper testing procedure, according to the service manual, is to disconnect the 12v battery negative terminal, then measure the voltage across the positive and negative terminals. That will effectively remove the battery from the equation...
I replied to this once, but my post got lost(?)
Thanks GeekEV for the tip -- I tried it and indeed the solar panel provides voltage to the system with the battery disconnected. Covering the panel causes the voltage to drop from 12 (or so) down to 1 or 2 volts, proving that the panel *is* doing something.
My faith is restored that it isn't a completely empty marketing ploy, at least.
EVerlasting wrote:I have been using a 1.5 Watt solar panel to keep my ICE cars and ICE motorcycle batteries topped up when I am not driving/riding the vehicles. Although it says 1.5 Watt, it only gives out a few milliamps of output current. The solar panel trickle charges the batteries very well. I have been using them since five years and the batteries are still working. I am very confident that Nissan Leaf's spoiler solar panel is even better than my cheap solar panel, so it definitely helps keep the 12V battery charged up. These solar panels work even in overcast, cloudy skies and even under fluorescent lighting in garages. Although the current is tiny under such situations, it still manages to prevent the 12V battery losing charge. If it is unable to increase charge, it will at least maintain the charge. Most batteries lose charge with time even without any power draw. Here's what I have been using, these are available with different name brands from different retailers but overall they are the same thing from China: