Make Battery Last Longer

[Mike90250]

........ I would even skip the zener, if the cells are never connected when the motor is off. Bruce Roe

That's a big IF One mistake, leaving the PV connected in the dark - will drain the battery. Parked in the sun between flights, might overcharge, depending on battery SoC.

So, I'd add a schottky diode as a reverse bias prevention, and a 5w zener as overvoltage protection.

[bcroe]

That's a big IF One mistake, leaving the PV connected in the dark - will drain the battery. Parked in the sun
between flights, might overcharge, depending on battery SoC.

So, I'd add a schottky diode as a reverse bias prevention, and a 5w zener as overvoltage protection.

That is important. I thought the switch (or connector) connecting the battery to the motor might
have an extra pole to connect the panels. Avoid a zener that size which needs a heat sink. Bruce

[cagiva]

I'd add a schottky diode as a reverse bias prevention, and a 5w zener as overvoltage protection.

Mike90250, Your suggestion was right on. Ditching the charge controller and just adding the schottky diode and a 5w zener has given us the best results. One question, do you see the need to also add a capacitor to the circuit? Thanks!

Orbit-Solar (1).png

[Mike90250]

Mike90250, Your suggestion was right on. Ditching the charge controller and just adding the schottky diode and a 5w zener has given us the best results. One question, do you see the need to also add a capacitor to the circuit? Thanks!

Great, I'm glad it worked. One thing worries me, you have a 12V zener as protection against overvoltage on a 11.1V battery, that seems to be beyond the safety margin by 1.5V or so.

The large capacitor is not needed, unless the zener generates enough noise/hash that it interferes with the plane's radio, then a much smaller capacitor, 0.1uF / 30V ceramic disc would help.

[cagiva]

Mike90250, We used the 12V Zener because this battery is at 12.4V when it's fully charged. Won't a lower 11V Zener attempt to bring the battery down to 11V(10.45-11.55)?

[jflorey2]

Great, I'm glad it worked. One thing worries me, you have a 12V zener as protection against overvoltage on a 11.1V battery, that seems to be beyond the safety margin by 1.5V or so.

If they are li-ions then they are good up to 4.2VPC, or 12.6 volts total. So a 12V zener should work OK as long as it doesn't remain connected during "normal" charging.

[Mike90250]

OK on the zener voltage. I just wanted to be sure there was not going to be a problem

[Mike90250]

They should adjust and counteract one another, including boards includes weight and drag, to counterbalance that you should add push capacity to produce more lift to convey a heavier plane, to do that requires more power from the power plant...

Where did that come from ?

[SunEagle]

Where did that come from ?

Oh snap. I deleted a few other posts by Oscar but must have missed this one. A member suggest this post and others may be cause by a "bott"