Replacing NiCd camcorder battery with NiMH

[Happy Friar]

I everyone
I would like to replace the NP77H NiCd battery on my Sony analogue
camcorder with a suitable NiMH one. The battery supplier says thier
NiMH batteries are fully compatible with the original battery and
charge. However Sony say that I should not use a NiMH battery and
should replace it with another NiCd. Does anyone have experience of
this.

Regards David Parkes

 

[DBLEXPOSURE]

I everyone
I would like to replace the NP77H NiCd battery on my Sony analogue
camcorder with a suitable NiMH one. The battery supplier says thier
NiMH batteries are fully compatible with the original battery and
charge. However Sony say that I should not use a NiMH battery and
should replace it with another NiCd. Does anyone have experience of
this.

Regards David Parkes

I belive it boils down to the chargers capabilities. If it is not
compatable with NiMH then do not do it. Perhaps you can find a third party
charger that can. If Sony says there carger cannot do NiMH then I would
belive them.

http://e-parts.netfirms.com

 

[Happy Friar]

Thanks for the reply. Sony did not actually say the charger would not
do it they were more interested in selling me one of thier batteries.
If I do decide to buy a new NiCd then it will not be a sony but a
compatible one. My camcorder is 13 years old and does not see much use
but is usefull at times. So what is the difference between charging
NiCD and NiMH.

 

[PeteS]

The charge profiles are somewhat different.

NiCd charge profile:
Constant current, usually time limited. Trickle charge ok. Advanced
chargers measure temperature and cell voltage and cut the charge to
trickle during the -dv/dt part of the profile. Peak voltage is not
usually an issue (because the peak voltage can vary so widely for NiCd)

NiMH Profile:
Constant current or current limited (fast charge mode). Peak voltage
detection required. Trickle charge ok. Charge controllers should
measure -dv/dt and temperature.

In general, most available charge controllers for these types of
battery handle both (NiCd / NiMH). (See, for example,
http://focus.ti.com/paramsearch/doc...aramTable=yes&sortOption=&sortMode=&pageId=64)

You may find it difficult to get new NiCd (or you'll pay a premium)
because of their chemical content (heavy pollution issues). I would try
and find out if your charger is NiMH compatible.

Cheers

Petes

 

[Robert Nichols]

:Thanks for the reply. Sony did not actually say the charger would not
:do it they were more interested in selling me one of thier batteries.
:If I do decide to buy a new NiCd then it will not be a sony but a
:compatible one. My camcorder is 13 years old and does not see much use
:but is usefull at times. So what is the difference between charging
:NiCD and NiMH.

http://www.greenbatteries.com/bachfa.html#charger differences

 

[quietguy]

I understand that NiMH batts lose their charge, when stored, much more
quickly than NiCds - I would find it annoying to discover my batts are
flat when I want to video something, so would choose to continue with
NiCds - but that's me.

David