scalebldr

My Feedback: (7)

after using nicads for over 33 years i see that rx and tx packs are being offered in nimh for half the price.being a bit relunctant to try something new as i like to use what i know works.what are the advandages and disadvantages of the nimh packs.what kind of charger is required?what kind of discharger is needed?i have had nicad packs last upto 10 years with proper care.what is life expectancy of the nimh packs?how does reliability compare between the two.most of the nicad problems ive had is when one cell in a pack develops an internall short and decrease the capacity of the entire pack.are nimh packs prone to this problem also or are they too new to tell.thanks for all the input in advance as i have not flown for two years and removed and sold all my tx packs at that time.now i have time to fly again and want to start replacing battery packs.i want the most reliable troublefree battery,cost is not an issue.when i am flying my b-24 or zirolli at-6 i do not want a disaster caused by a 20 buck pack if a 40 buck pack would have made a difference.i always considered the batteries the weakest link in the system.

Geistware

My Feedback: (16)

Try Red's place http://www.rcbatteryclinic.com/

Wildmann

My Feedback: (3)

Look at NoBs add in classified
for nimh batteries

Red Scholefield

My Feedback: (9)

For durability, resitance to abuse, tolerance to over charge, ease of charging, fast charge capablility, long service life Ni-Cd packs from Sanyo (via most hobby suppliers) are hard to beat.

scalebldr

My Feedback: (7)

after reading what i found ay yhe link provided by Geistware i have concluded that it is more prudent to stay with nicads for all the reasons stated above cost of batteries vs cost of plane is not an issue here.you get what you pay for comes to mind also.thanks

rajul

My Feedback: (58)

Check out Dave at radicalrc.com for the best NiCd packs. I've got all my supplies from him, including extensions and switches and I can attest to the product quality and reliability. He charges exact shipping, no overcharge

Flying Geezer

My Feedback: (14)

I agree with Red, don't fix it if it isn't broken. No offense to the guys who like to be on the leading edge, but I have yet to see any noticeable advantage to nimh. Ok, I'm old and set in my ways.

I was given a nice digital camera for Christmas. I was pleased with the thoughfulness, but didn't see any advantage over the trusty Minolta (film camera) that I have had for years. After playing with it for a while, I found some real technological advantages, and I'll never have to buy film again. Now that's an advantage.

Happy New Year everyone,

rajul

My Feedback: (58)

Well, you did make the switch to digicam. So, I guess you're not that bad. LOL !

Hangtime

My Feedback: (19)

Not all cells are created equal. A NiMH cell from Panasonic or worse, some of the chinese sources are pretty scary things to be using as Rx packs. Sanyo's NiMH cells are very good choices if you need the advantages of long run time or lighter weight at the same capacity as NiCad. If I run NiMH as an Rx pack it's usually as a 5 cell pack to stay well ahead of the voltage drop under load characteristic. As with anything else, a quality brand cell from a quality US based hobby assembler can make all the difference.

NiMH vs NiCad is a debate that will rage on for many years to come. I've known Red for 15 years now.. never known him to steer anybody wrong, and what he's saying is correct.. NiCad still holds the durability edge in the brutal world of high current draw and fast charge applications.

One place NiMH has found a happy home is in Tx applications.. a 1650ma Tx pack in a 9CAP is a wonderful thing on a long summer day at the field.

I've posted a NiMH FAQ on my website (link below) if anybodys interested in exploring some of the more common questions I've gotten on NiMH over the years. Success with NiMH depends on knowing how to take care of 'em, where to use 'em and making sure the charger can deal with 'em correctly.

Cheers, All!

Hangtime
[ul][*] www.hangtimes.com[*][*] [/ul]
NoBS Batteries

AJF--2

My Feedback: (119)

I know a lot of people are going to laugh, but for the best peace of mind I buy SR batteries. I got one in a plane that I bought and I know that it was at least 5 years old and I thought it was time to discard it. WELL LET ME TELL YOU THAT AFTER A CYCLE OR TWO IT WAS OUT PERFORMING ALL OF MY NiMih of the same size and just a few months old! That made a believer out of me. If you don't mind the extra weight and especially if you use a lot of digitial servos like me, the Nicad is the way to go. And for the undisputed leader in high quality Nicads, it is SR (in my humble opinion, anyway) Now I just use the Nimah for ignition systems.

Red B.

Hi!
I posted the text below rather a long time ago as an answer two a question about NiCd vs. NiMh, perhaps you will find it useful:

Some "facts" about NiCd and NiMH batteries

*The NiMH delivers roughly 40-50% more capacity than a NiCd of the same size.

*NiMH batteries are considerd to be more environmetally "friendly" than NiCd batteries.
Cadmium is a nasty metal!

*The recommended discharge current of NiMH cells is considerably less than that of the NiCd. For best results, manufacturers usually recommend a load current of 0.2C to 0.5C. For high current applications, such as when using several digital servos, the more rugged NiCd is the recommended choice.

*Both NiMH and NiCd are affected by self-discharge . The NiCd loses approx. 10% of its capacity within the first 24 hours, after which the self-discharge settles to about 10% per month. The self-discharge of the NiMH is approximately double that of the NiCd.

*The NiMH is usually rated for only 500 charge/discharge cycles. Shallow rather than deep discharge cycles are preferred. The battery’s longevity is directly related to the depth of discharge.

*Memory effects in NiCd cells, meaning that a NiCd battery can remember how much discharge was required on previous discharges, is a thing of the past
There is however other effects to be considered, the most important one being crystalline formation. The active materials of a NiCd battery (nickel and cadmium) are present in finely divided crystals. The crystal should be as small as possible in order to maximise the surface area. Under certain circumstances the crystals grow and drastically reduce the surface area. The result is a voltage depression which leads to a loss of performance. Some of the capacity may still be present but cannot be retrieved because of the battery’s low voltage. In the end the crystals can become so large that they cause an electrical short in the cell.

The effects of crystalline formation are most pronounced if a NiCd battery is left in the charger for days, or is repeatedly recharged without a periodic full discharge.
In order to avoid crystalline formation it is often recommended to cycle NiCd batteries once per month. Between these monthly exercise cycles, no further attention is needed and the battery can be used with any desired user pattern without the concern of memory.
NiMH batteries are less affected by crystalline formation and because of its shorter cycle life it is sufficient to cycle the batteries once every three months.

In the end the choice is yours!

/Red B.

Hangtime

My Feedback: (19)

Why; thank you! I built that pack... and spent better than a decade as that companys Operations and Production manager.

The reality is that comparisons between Nicads and NiMH in duty cycle lifetimes, load perfomance, storage and durability are an exercise in 'orange vs apple' debate theory. Whats beyond dispute is there's places for both technologies in the hobby.. In fairness, comparsions involving NiMH cells should be left to comparisions amongst cell manufacturers. As I pointed out earlier, a Sanyo NiMH is a heck of a lot better choice than a Panasonic (hydramax) or some other bargain-basement low quality mfg's NiMH cell.. and there are a huge number of these 'cheapo' NiMH cells being dumped into our hobby recently. The same is true with regard to NiCads, and I can assure you from my own personal experience (and yours) that among NiCad cell Mfg's theres none better than Sanyo.

Cheers!

Hang
www.hangtimes.com