battery science

[gavinkempsell]

Just a simple thought of... Oh, toastie! has led to this question.

charging my batteries for Sundays game of playing soldiers, I noticed my lipo's don't seem to get warm when charging (not noticably anyway) , but my Ni-MH's do, so what's the science to this please?

for reference I use a Nuprol Power Compact Intellegent charger. it's used on the correct setting for each type of battery (not making that mistake again) & it's never left unattended.

 

[Sewdhull]

Nimh get warm when they are full and are kept charging.

They rely on the detection of a small drop in voltage at full charge to stop charging and if that is not detected correctly the temp will rise, basically because no more charging can be done and the continued current heats the cells. If no balance charging is possible, some cells may be full while the others catch up and the full cells will warm.

Some chargers used a probe to detect the temp rise and stop charging.

Lipo uses a voltage limit to stop charging, with a reduction in current as it gets close to the cut off voltage, which is straightforward.

https://batteryuniversity.com/article/bu-408-charging-nickel-metal-hydride

 

[Shamal]

Just a simple thought of... Oh, toastie! has led to this question.

charging my batteries for Sundays game of playing soldiers, I noticed my lipo's don't seem to get warm when charging (not noticably anyway) , but my Ni-MH's do, so what's the science to this please?

for reference I use a Nuprol Power Compact Intellegent charger. it's used on the correct setting for each type of battery (not making that mistake again) & it's never left unattended.

Click to shrink...

Pies tend to get very hot.....?