12V 60A car battery , maybe dead?

[gezgin]

@Groundloop,
Finally i added L3 coil and testing your circuit .I used 220 ohm/5 watt resistor instead of R2.
Here is outpu coil waveform :

thanks.

[Groundloop]

@gezgin,

I do not know what voltage scale you use on your scope but the pulses looks OK to me.
So how is your battery doing?

[EDIT]
Sorry, did not see the 10 Volts/Div text right away. So the output spikes is bigger than 12 Volt?
What input are you running at?

Groundloop.

[gezgin]

battery still low 11 volt..
output spikes is bigger 12 volt,  maybe 30 volt because scope probe is x10 position.(you can see with this photo )
your circuit is interesting,  i can see multifrequency pulses 10 ms, 60 usn..

[Groundloop]

@gezgin,

Hang in there. If the battery has gained to 11 Volt and the battery does not heat up, then
just push on. Keep the input voltage to the charger below 11 Volt so that just the high
voltage pulses is "hitting" the battery. When the battery has passed a rest voltage of 12 volt
then you can turn up the input voltage a bit. Just keep on charging. It takes time for the
battery to recover. Maybe later you can mount the charger into a nice plastic box? :-)

Groundloop.

[hartiberlin]

You can now also put the power supply voltage to about 14 Volts.
But then monitor the battery voltage and don?t let it runover night
or when you are not there.
When the battery begins to gas out, please be careful and
shut it down.
Don?t unplug the plugs directly at the battery as this could
cause a spark and the HHO gas might explode inside the battery.
Shut down the external power supply instead.

Let us know, what comes out of it.
Many thanks.

Regards, Stefan.