Uploaded June 2023 | Updated September 2026, 2 weeks ago
This circuit came into existence with the help of others, thank you for sharing about splitting the negative.
Once I looked at polarities I saw I could use battery 2 also as the battery charged by the cold.
So we have 2 charges coming in on bat 2, the 12V dc difference between - connection of dc-dc converter and - pole batterie 2, and the charging coming from the cold electricity.
From now on I will call the spike coming back from motor coils the cold electricity and not the negative, otherwise it creates confusion with polarity.
Splitting the negative is about polarity of input source.
Here are my test results with 2 batterie system with DC-DC converter and split the negative
Start experiment, everything connected (dc-dc converter powered up), motor not running
Bat 1 Bat 2
15:00h 12.76V 12.58V
Start motor
12.65V 12.73V 1.15A ( current measured on blue wire Bat 1 )
15:30h 12.52V 13.18V 1.2A
16:00h 12.49V 13.25V 1.22A
Stop motor & change batteries
Bat 2 Bat1
16:02h 12.78V 12.73V 1.17A
16:32h 12.42V 13.1V 1.24A
17:02h 12.38V 13.19V 1.25A
Stop motor & remove inductor after startup
17:05h 12.36V 13.25V 1.65A
17:35h 12.35V 14.11V 1.54A
18:05h 12.36V 14.95V 1.43A
Stop motor & change batteries
Bat 1 Bat 2
18:10h 12.9V 12.58V 1.71A
18:37h 12.53V 12.9V 1.68A
19:07h 12.45V 13V 1.67A
Stop motor
12.61V 12.84V
Bat 1 starting at 12.76V ending with 12.61V (-0.15V)
Bat 2 starting at 12.58V ending with 12.84V (+0.26V)
After an hour battery 1 was 12.69V (+0.8V) and bat 2 was 12.71V (-0.13V) (unloaded)
Batterie 1 is the one that did go to almost 15V in the test.
This circuit came into existence with the help of others, thank you for sharing about splitting the negative.
Once I looked at polarities I saw I could use battery 2 also as the battery charged by the cold.
So we have 2 charges coming in on bat 2, the 12V dc difference between - connection of dc-dc converter and - pole batterie 2, and the charging coming from the cold electricity.
From now on I will call the spike coming back from motor coils the cold electricity and not the negative, otherwise it creates confusion with polarity.
Splitting the negative is about polarity of input source.
Here are my test results with 2 batterie system with DC-DC converter and split the negative
Start experiment, everything connected (dc-dc converter powered up), motor not running
Bat 1 Bat 2
15:00h 12.76V 12.58V
Start motor
12.65V 12.73V 1.15A ( current measured on blue wire Bat 1 )
15:30h 12.52V 13.18V 1.2A
16:00h 12.49V 13.25V 1.22A
Stop motor & change batteries
Bat 2 Bat1
16:02h 12.78V 12.73V 1.17A
16:32h 12.42V 13.1V 1.24A
17:02h 12.38V 13.19V 1.25A
Stop motor & remove inductor after startup
17:05h 12.36V 13.25V 1.65A
17:35h 12.35V 14.11V 1.54A
18:05h 12.36V 14.95V 1.43A
Stop motor & change batteries
Bat 1 Bat 2
18:10h 12.9V 12.58V 1.71A
18:37h 12.53V 12.9V 1.68A
19:07h 12.45V 13V 1.67A
Stop motor
12.61V 12.84V
Bat 1 starting at 12.76V ending with 12.61V (-0.15V)
Bat 2 starting at 12.58V ending with 12.84V (+0.26V)
After an hour battery 1 was 12.69V (+0.8V) and bat 2 was 12.71V (-0.13V) (unloaded)
Batterie 1 is the one that did go to almost 15V in the test.
