I'm actually ashamed to admit I've been around this hobby off and on for over 10 years including a nearly 3 year stint at HobbyTown, but for the life of me I don't know jack about batteries.

For a receiver pack, what are the pros/cons of NiCd vs. NiMh? While I'm at it, the pros/cons of a 4.8V pack vs a 6V pack? Obviously more output from the 6V, but is there a downside? I'm going to be picking up a couple of 1500 mAh packs for the Funtana and the Decathlon and just want to make sure I get the most suitable packs. Thanks.

I second that question, I had always used the NiCd type for reciever packs but the last couple times I was in Hobby town I bought what they had and wound up with NiMh , the down side of that to me is keeping track of what is in what when charging them up, I have to stop and think (and you all know how hard that is for me) which type is in it. wish I could go back and stick to all NiCd's.

This didn't help you any Mike but just adding my :twocents:

Basically nihm and nicads are pretty close. One thing to look at is the application.

If you're looking for a battery that can handle high discharge rates, like using them in an electric plane with a brushed or brushless motor, then the nicad will handle the discharge and heat better.

Nicads can develop a 'memory' after time. If you repetatively only fly a couple of flights then charge with no cycling the battery can develop a kind of short length memory to where the battery will die quickly after the norm time span that it's used to. This isn't an automatic, do it twice and it will happen thing...

Nihm's hold more capacity (20-30%) and weigh a little less. It will hold it's voltage for a longer period of time. Nihm's though will drop their voltage quicker than a nicad when they get close to the end of the charge. Nicad's gradually drop their voltage over the use time.

4.8 vs 6 volt. Once again, depends somewhat on the app. If you're looking to get quick response out of your servos then the 6 volt will quicken the servo rate. It adds just slightly more weight to the model as there are 5 cells instead of 4.

Most chargers now accomodate both nihm and nicad and are automatic so it's really not not inconvienient

I use both. The nicads that I use are just some older ones that I have around. I either use nihm or li-ions or polys now.

All that Jon said, plus:
If you go with a five cell pac, use a voltage regulator to keep around 5.5 volts going to the electronics. Freshly charged five cell pac will be well over six volts for a good part of it's discharge time period. Could start as high as about seven volts and some receivers, gyros, servos might not like that high a voltage.

To make for full capacity on NiMh pacs, do first couple charge discharge cycles on overnight charge rate after full discharge (like down to 1.1 volts per cell). Then you can go with the fast field charging.
Talking flight pac use - Some NiMh cells have higher internal resistance than desired for high drain use, like all digital servos. Use of non-digital servos should not present any problem for any NiMH battery.

This is complicated stuff. So what you're telling me is that since the only chargers I have are standard issue Futaba wall chargers, and I don't have or want to purchase a voltage regulator, I need to stick to a 4.8V NiCd pack. I can handle that. B)

C'mon, Mike, it's not complicated at all! You seem bright, so get with it... :rolleyes:

I use both NiCd and MiMh. I prefer the NiMh packs for the reasons stated... :thumbup:

The Futaba wall chargers will charge either the NiCd or MiMh packs.
For a long-term, low amperage charger the difference is minimal. I never worry about which charges what...

My Hobbico MK-2 quick field-charger has settings for NiCd, NiMh and LiPo, so if you can read, you'd have no problems there either... Just don't charge lithium packs on the NiCd and MiMh settings. :yickes:

Oh, well....as long as my Futaba wall charger can handle the NiMh packs I have no problem purchasing them. Standard 12-15 hour charge time I take it? Thanks. :)

Yep...That is pretty much it.

Well, I picked up a pair of 6V 1500 mAh NiMH packs tonight. And EVEN THOUGH my Futaba wall charger says on it "use only for NiCd batteries," I'm charging one of them up with it anyway. I'm nervous! :lol:

are you reallllly useing a wall charger? :huh:

Yes. I predict this is you trying to scare me.







Well it's working, I'm searching RCU now. :angry:

it will work you just might have a problem of a 4.8v 100mha charger trying to charge 6 volts, it will never get you there

Yeah, I figured that. This will get it charged enough to get everything (servos, etc) set but I'll be needing a new charger. And I didn't even think to look while I was at the shop tonight.

Mike,
I doubt that the 4.8 charger will charge the five cell packs much. The battery might charge the charger.

Why did you decide to go with the five cell packs?
Curious minds want to know. :unsure:

Did you also know that five cell pacs will explode after a couple of hours exposed to rap music. Be carefull. :lol:

Because I let Justin talk me into it since I'm running some powerful servos in the Funtana and in the Decathlon. I know it's probably not necessary, I just got caught up in the excitement. Should've stuck with the 4.8V packs and save myself the trouble of having to get another charger right away. :angry:

I think I'm going back to HobbyTown tomorrow to set things right. Whether that means returning the 6V packs for 4.8V packs or getting a new charger has yet to be decided.

Check it all out some more before final decision.
Big high performance servos might need the extra voltage.
A wall wart charger for them would not be all that much.
Do some more research on the voltage regulator thing when useing five cell pac.

well 6 volts is fine, every pack i have is 6 volt for planes and choppers. give you that extra little power makes things faster.

just watch out for the rap music thing,,,, :hysterical:

One Hobbico MkII field charger later, and I'm all set. Now, if I can get my hands on a 12V power supply I'll be golden. You hear that Steve? :D

Will the MkII put a slow first charge on the batteries? Remember you always want to put a good slow charge on a new battery and cycle it a couple of times to make sure it comes up to it's holding voltage... Ask me how I know :unsure:

Thought I already hooked you up? If not I am sorry, I was planning to put one together for Alvin by this week end, I'm sure he won't mind delaying his another week so I can get you one ready. :D

:lol: You'll never guess what I'm reading up on right at this exact minute....it's how I need to form these packs at C/10 and the MKII won't do that!!!!! Like I said, it's never easy! I need a 6V 150 mAh wall charger, anybody got one I can borrow for a few days? I'll come pick it up tonight.

I have a hobbico cycler that I'll loan you for a couple of days...

649-3716

Not that Alvin needs one and has been promised for a month...Noooooooooooo...Fix Mike up first by all means.
I see how it is now. :angry:

LOL ... don't worry I have been needing one myself and haven't made the time to make myself one. The list is Alvin 1st , me 2nd and Mike 3rd but I hope to get them all done by saturday so no one has to whiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiine at me anymore. After that I am done taking orders, I'll be glad to tell anyone who has a power supply how to rig it up but my supply is thinning out, I ran across a couple bad ones trying to fix up one last week end.

Well, make sure mine is a good one.
My mental state will not allow for troublesom electricals. :(
And don't forget the little metal plug things that stick in the + & - holes that you attach the aligator clips to. :unsure:
And the cooling fan needs to be working. :paci:

This aint no "custom 12 V power supplys are us"

Can you make mine yellow to match the Funtana and the Decathlon? :D

Jon, thanks again! I even brought the cycler to work with me so I can switch it over to discharge as soon as it finishes. :thumbup:

lol

Steve delivered to me my new 12 volt power supply.
He did a great job on it with purple anodized case and chrome accents.
And a twin yellow racing strip right down the middle.

I am so so happy.
Thanks a bunch Mr. Steve. :yes:

Steve,

Maby Alvin will take away some of those warnings he gave you a few weeks back :thumbup: :)

NO!! , I don't want that, I am collecting them. :fullmoon: