Do NiMH Experience -ΔT ?

[Wabatuckian]

K peeps, I've got a dumb question for you:

Do NiMH batteries experience -ΔT like NiCad do? I was playing with my new NiMH battery pack, trickle charger, and a multimeter, and never saw the voltage drop.

Pic for attention, rapid charging the old NiCad. That's a big ol' heatsink everything's setting on.

 

[bill_delong]

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

The charge algorithm for NiMH is similar to NiCd with the exception that NiMH is more complex. Negative Delta V to detect full charge is faint, especially when charging at less than 0.5C. A mismatched or hot pack reduces the symptoms further.

NDV in a NiMH charger should respond to a voltage drop of 5mV per cell or less. This requires electronic filtering to compensate for noise and voltage fluctuations induced by the battery and the charger. Well-designed NiMH chargers include NDV, voltage plateau, delta temperature (dT/dt), temperature threshold and time-out timers into the full-charge detection algorithm. These “or-gates” utilize whatever comes first. Many chargers include a 30-minute topping charge of 0.1C to boost the capacity by a few percentage points.

 

[Wabatuckian]

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

Cool, thank you. I tried googling it and only came up with a bunch about charging EVs.