# NiCad Life Expectancy



## rsmproductions (Jan 5, 2008)

Greetings Everyone,

I have an RC/rechargable battery system in a Connie that I've been running for about two years. I don't run it every day but on special occasions. A few weekends ago I brought it out for my son's 3year birthday party and was dissapointed that the train couldn't run more than about a 1/2 hour. I tried the main "tender" power supply and then the trailing car power supply and both seemed to not want to run. The sound turns on but sounds sluggish and has static. All the batteries are Exell 6/2000SC(T) purchased from Dave Goodson who helped me with the RC/Battery install. 

Have I exhausted the batteries and need to purchase new or could there be something else going on?

I appreciate any help you may give.

Thanks,
Richard


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## Curmudgeon (Jan 11, 2008)

Odd. 
Generally the 2AH batteries in a 2-8-0 get 3-4 hours each. 

What charger? 
MAHA? 
It will cycle them, if you select it, and when it comes back up will tell you the volts and amps. 

Or, charger could be bad, whatever it is, or power supply. 

30 minutes really sounds like it didn't get charged. 
Especially if both sets did exactly the same thing. 

Our NiCads get used a lot, and last 5-8 years. 

Call me. 

If you tried e-mail, earthstink has had some interesting issues of late.....


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## rsmproductions (Jan 5, 2008)

I thought the batteries were supposed to last quite a while. I charged them overnight just to make sure they were ready to go prior to my son's 3rd BD party. Perhaps it's not the batteries at all but something else. In the past when I have run the engine it just kept going and going...and with the trailing car I could run longer than the actual duration of the event. It wasn't unitl about month or so ago and it was really humid outside and the engine just slowed to nothing. Almost like the signal wasn't getting to the engine from the transmitter. I figured the air was heavy and perhaps that was the cause of the sluggishness.

And yes I have the MAHA battery charger. I wonder if I discharged each battery and then recharged them if this might make a difference.

On a side note...I have a Heartland Disneyland Lilly Belle (not the live steam version) and wondered if it could be outfitted with RC and battery. I haven't looked in the tender but it is smaller than the Connie. 

thanks,
Richard


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## Torby (Jan 2, 2008)

Call the TOC, he'll make it right for you. He's good people. He has *earned *the right to be Curmudgeonly. On the other hand, I'm just a brat.


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## Greg Elmassian (Jan 3, 2008)

Good nicads can last through many cycles, if properly treated. I have some more than 20 years old. 

Cheap ones, or batteries improperly maintained can fail quickly. 

The Maha is a great charger, put the batteries through a full charge, then the discharge cycle, the end of the discharge cycle will tell you the amp hours the battery really have. 

No need to speculate when you have the tool to figure it out. 

Regards, Greg


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## Totalwrecker (Feb 26, 2009)

Heavy air? An extra isotope? I don't think so.... 

Humidity however can get into a cold sloder joint and disrupt the circuit, you might want to check your circuitry for continuity... but I'm no expert. 

John


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## rsmproductions (Jan 5, 2008)

I appreciate the responses...

I have been testing the NiCads today and trying to make sure I'm running the MAHA charger correctly. Here is where I am so far.

One of the NiCads was discharged and recharged. The "full" signal showed just a few minutes after charging with an mAh of 114. I let it be for a while with no change or increase in mAh. I have plugged in the second battery and am awaiting a "full" signal.

So does anyone have an idea of why I might be getting only 114 mAh on one of the batteries. Is this a signal the battery is bad? or do I need to recondition (if possible)...I'm fairly dumb when it comes to batteries and how everything works.

Richard


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## rsmproductions (Jan 5, 2008)

Ok...second battery charged at 1499 mAh and fully charged according to the charger. I am discharging the 1st battery again in the hopes of conditioning back to full power...we'll see.

Richard


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## Greg Elmassian (Jan 3, 2008)

You are not quite getting it. The key is discharging, that's your "run time". If you re-read what I said:

"The Maha is a great charger, *put the batteries through a full charge, then the discharge cycle, the end of the discharge cycle will tell you the amp hours the battery really have.* " 

you charged the batteries, but did *not *discharge them... there was only 114 ma of charge necessary to bring them to full... 

Now discharge them and measure what they really can put out... 

Do you still have your manual? 

What you did is take a car to the gas station and topped off the tank. Now you need to drive it until it's empty and check your speed and distance... the Maha will show that... does this better explain the concept?

If you don't have the manual, you can download it from the web. 

Regards, Greg


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## rsmproductions (Jan 5, 2008)

Hi Greg,

I appreciate what you are saying, and yes I have the manual and have read it over several times today. 

I can only say that the first time I followed the directions to press the discharge button. When I heard the beeps that it was complete I charged the battery back up and only got a total of 114 mAh. I followed the same steps for second time and now am charging at 1488 mAh and increasing as I write. I am wondering if the original condition of the batteries were so depleted that when recharged they only charged a small amount...similar to cell phone batteries. I know my phone instructions recommend letting the battery fully drain every now and then before recharging to keep up the health.

It seems to be getting better at any rate. I still have the tender car to recharge...

Thanks,
Richard


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## rsmproductions (Jan 5, 2008)

Well, the one battery that registered the 114 mAh earlier was discharged a second time and then recharged to 2064 mAh....so it seems that this battery is back in business. I am now discharging the second battery so I can recharge it in the hopes of fully charging it.

Will keep you posted.

Again, I appreciate all the input and I feel that I am able to better understand the whole rechargable battery thing so as to avoid this in the future.

Richard


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## Greg Elmassian (Jan 3, 2008)

OK, but I have to tell you again... 

The amount that goes into the battery is NOT the capacity... the amount discharged is... you have to look at the discharge amount... 

For example, an internally shorted battery could take forever to charge and show hundreds of amp hours... 

There is a "trick" to stopping the automatic recharge after discharge, you press and hold the discharge button and you get another beep if I remember right. 

Then it will discharge and stop showing the discharge amount, i.e. the true capacity. 

If you just put the battery on the charger and hit discharge, then it discharges, beeps, waits a short bit of time and recharges. That window of time is pretty short to see the discharge specs. 

(now, of course, it seems in your case that the battery needed some conditioning, and USUALLY a longer charge time with more amp hours registered NORMALLY means things are getting better, but it is not for sure) 

By the way, the "trick" is no longer in the manual, I have an old manual that described this, but it's not in the new manuals... if I remember correctly the discharge indicator does something different, like blink, or stay on steady.. 

Regards, Greg


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## Del Tapparo (Jan 4, 2008)

The charger I use for my NiMh (Elite Pinnacle+) often gives me a false peak and terminates charging prematurely. I hit the charge button again, and it then takes a full charge. However, this usually happens right after a run, when perhaps the battery is still warm. This may not apply here, just relating my experience.


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## rsmproductions (Jan 5, 2008)

Hi Greg, 

I think the "trick" you are referring to is the "annalyze" function where you hold the discharge button for 3-5 seconds, it then applies 3 minute charge and then commences the discharge. At the end it freezes so I am able to see the true capacity. The second battery didn't do that...I didn't hold the button long enough. It was still discharging when I went to bed last night and automatically recharged. 

I am testing the tender batteries now to see what the capacity is...so If I understand what you are saying...the number in mAh at the end of the discharge is the "true capacity"? So if it is 114 like the first time what do I assume?? To me an original spec of 2000 down to 114 is a loss of 1886...am I looking at this correctly? 

I appreciate your knowledge and patience in all of this. 

Richard


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## Greg Elmassian (Jan 3, 2008)

Richard, I may have misunderstood you, I interpreted what you said to mean that the battery only charged to 114 ma on the charge cycle. 

Yep, sounds like you got the anaylze function working, but you need to be sure the battery is fully charged first, so a 3 minute charge is no guarantee that the battery is fully charged. 

Yes, the milliamps at the end of a discharge cycle is the true capacity, because that is what you are buying, the ability to provide power (discharging) of a certain amps over a certain time. In our hobby we rarely if ever have to discharge at full capacity, i.e. a 4 amp hour battery providing 4 amps for an hour. But, often it is 1/2 C rate (C is the Capacity in amp hours), so you would hope to get 2 amps for 2 hours from this battery. 

Nicads left discharged or not used often will develop internal shorts that will reduce the capacity of the battery drastically. Sometimes you can recover a battery like this, but not normally back to full capacity. 

Anyway, sounds like you are on the "right" track now, 2 or 3 full charge/discharge cycles should tell you where the battery stands. 

Regards, Greg


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## Gary Armitstead (Jan 2, 2008)

Hi Greg, 

That's great information regarding the "trick" in discharging. I bought my MaHa from Jonathan in late 2007 and my manual doesn't show this trick. I have been having erractic charging with my batteries lately. My stuff is not run that often so I charge them every 90 days and then store. I charged them about 45 days ago and haven't run. I think I'll try your trick today and see what the results will be. Any other suggestions greatly appreciated. BTW, my batteries are NIMH and the charger is the MaHa MH-C777Plus-II. THX


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## rsmproductions (Jan 5, 2008)

Sunday Update...

I've been working on the tender car's two batteries trying to recondition and see how far I can bring them up. The first attempt at discharging in the "analyze" mode yielded a lofty 68 mAh. The recharge didn't go much higher and took only about 7 minutes to achieve a full charge. I am discharging a second time now with a current reading of 380 mAh. I am hopefull that after a couple of cycles I might be able to regain some power in these batteries.

Will keep you posted.

Thanks to all that have given their thoughts. I'm feeling like I know a bit more now about all of this rechargable battery stuff.

Richard


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## Steve Stockham (Jan 2, 2008)

I have consulted with some battery experts as I have to deal with NiCad and NiMH batteries in Exit/Emergency lights as part of my business and what I was told is that these type o batteries can develope a "memory" whereby charging and run times will get cut drastically. I think this is just another way of saying what Greg told us. It's not quite that the battery was nearly full so it only took 100 or so to show full but that the "memory" of the battery became that_ becausethe battery wasn't fully discharged before charging again! _Supposedly, you can "reset" the memory by fully discharging your battery and then fully charging it. I was told this can sometimes take two or three discharge/charge cycles to accomplish. I have tried this and it seems to be so. I had the same trouble with my K-27. I first had a run of _six hours_ but after having let it set for a couple months I topped off the battery and the run was about 30 minutes! I ran the charge/discharge procedure three times and now the K is running about four hours give or take 20 minutes. 

One other point that my "expert" told me: Temperature is a critical factor in the life of a NiCad or NiMH battery! Temperature fluctuations of more than 35 degrees from 70 will cut the life of a battery in _half!!_ Storage of engines and battery cars in area that experience below freezing temperatures is definitely NOT recommended! It can cut the life of a battery down to_ 1-2 years!_


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## Gary Armitstead (Jan 2, 2008)

THX Steve, 

Good information. When I talked to Jonathan a year ago, he told me that sometimes you can get a "false peak". This is apparently what happens when you supposedly reach full charge after a very short charge cycle.


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## Totalwrecker (Feb 26, 2009)

Thanks Steve, 
What about high temps? Are they as destructive? I often am in the 110+ temps, had a week of 116 this summer. 
Should I put the batteries an a gas/mechanical reefer or will an iced reefer do the trick? Seriously tho' even a fan on those days wouldn't have lowered the temp below 116 which falls in that +35 degrees. 
I'm planning on an outdoor trainshed and it's too far from my house to run an ac conduit to it, will my temps kill my batteries; NiMH? 
Thanks, 
John


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## Greg Elmassian (Jan 3, 2008)

Steve is 100% right. And high temperatures in ANY battery shorten it's life. There ARE some batteries built to BETTER withstand heat, but it's never good. 

The "myth" of battery "memory" is often hotly argued, even among professionals who have been in the business for a long time. 

In nicads, the typical "memory" problem is caused by growth of conducting crystals, called dendrites. If you think of the battery as 2 large plates separated by electrolyte... if you put a nail on one plate sticking into the electrolyte, then the electricity takes the shorter path from one plate to the tip of the nail, instead of through the rest of the electrolyte to the "far" plate. 

When you apply a charge, only the electrolyte between the tip of the nail and the other plate gets charged. Consider a "forest" of these little conductive nails stuck to one plate (or the other)... basically you have reduced the volume of the electrolyte by bypassing it with the "conductive nails" (dendrites). 

Thus you have reduced the capacity of the battery. 

Now, it has been called "memory" because improper (or lack of) charging will let these dendrites grow... they crystallize out of the electrolyte under certain conditions... so the "cell" remembers not being used... memory... 

Also, the old wives tale of fully discharging before recharging has SOME basis in truth.... these dendrites, being small "short circuits" will take current first... in a completely discharged battery, under initial and HEAVY charge, a whole bunch of current will flow... it can be concentrated in these "shorts", the dendrites, since they are more conductive than the electrolyte around them.. 

Given enough current (which is normally enhanced by low resistance of a completely discharged battery) you can vaporize these dendrites, and somewhat recover the battery... that's also why the old practice of "zapping" a bad cell with a big capacitor sometimes works... 

But, normally, the conditions that got you in trouble are still there (poor charging equipment, lack of use, etc), so you maybe get a little more life from the battery, and always somewhat reduced capacity... basically the cell is damaged.. 

Hope this is not boring, but it's information about what really happens, there is no "memory" per se, just damage from poor handling... 

By the way, overheating the electrolyte often causes a catalytic action that changes the electrolyte, and of course, reduces it's ability to store a charge. 

Regards, Greg 

p.s. I was confining myself to nicads here, did not want to bog down the thread in the other chemistries, situations are similar but not the same.


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## Steve Stockham (Jan 2, 2008)

Ah! _That_ explains it! I now make sure to keep the batteries fully charged and to exercise them fully before recharging them! Thanks for the technical answer Greg! It actually made sense to me and considering it's me we are talking about, that's saying something!


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## Greg Elmassian (Jan 3, 2008)

I made friends with a TRUE expert on batteries about 20 years ago, he took me under his wing and explained many many things, and was the first person to explain the "myth" of nicad memory. He retired and gave me all his research papers and datasheets on batteries. I've "kept in the loop" ever since... through work and hobbies, keeping as current as possible. 

Thanks for the compliment! 

Regards, Greg


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## rsmproductions (Jan 5, 2008)

Here is an update to my situation and my Nicads...It has taken several discharge and recharging times to get my Connie's tender batteries close to normal. The last charge yielded in the 1400's mAh. It just takes quite a while to do all of this especially with a normal work schedule, etc. I'm hopefull to bring these batteries back to a somewhat good life. 

I have really learned a lot and thank all of you, especially Greg for sharing the expertiese on this whole rechargable battery stuff. 

I've been away from the hobby for a while just due to life's business but have got the fire burning again (now that the weather is much cooler!!) 

Richard


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## rsmproductions (Jan 5, 2008)

Whoo Hoooo!!!

Just got home and the Connie tender batteries discharged to a total of 2002 mAh!! So now I'm charging them back up to full...hopefully they will now last a bit longer. Now I need to do some more work on the trailing car batteries....might even be able to run the train this weekend.

Richard


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## rsmproductions (Jan 5, 2008)

After a week of on and off charging and discharging the NiCads in my Connie's tender as well as those in the tender we did a test run tonight and the engine performed beautifully.

Just want to again thank all of those for the help and suggestions. I now know so much more about rechargable batteries that hopefully I can avoid this in the future.

Thanks,
Richard


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