excuse the delay
I created this new topic because the conversation of the batteries was already off topic
This is the continuation of the discussion on topic: tuning-the-motor-using-the-neon-bulb-t50-30.html
"We are off topic here so maybe you should start a new thread in the batteries section.
Yes C20 is about discharging in 20 hours. If you have a 12v 10Ah battery and we want to discharge that in 20 hours we divide 10Ah by 20h to give the discharge rate. That is 0.5 amps.
We then choose a load that will draw 0.5 amps and time how long it takes to discharge. If the battery is in reasonable condition it will discharge in 20 hours + or – 10%.
If there is a big difference there is a problem with the battery.
Lead acid batteries slowly shed material from their plates, if half this material has gone you will have half the capacity. Drawing power at a higher discharge rate will cause more material to be lost.
If you battery has only 1/10th of its rated capacity I would use a smaller amp draw till it recovers as the plates that are working may suffer further damage but for charging I would use the C20 charge rate and drive the voltage as high as it will go when charging.
Can you check the specific gravity of the acid? You may need new acid if it is too low."
yes, my batteries need acid, I measured the weight of water and these are the pictures of the measures, also measured in a functional battery to make sure that the problem was not the measuring device
Today, after the black battery being charged (11.6V) called to a motor, it is possible to register a current of 50mA, it was 6 hours to discharge, after 6 hours the voltage on "disconected battery" was 9.6V, the engine was still working
I can do something to regain some of these batteries?