Nicad and NIMH guru's...Some ideas on radio battery charging

[saberjerk]

Hi
I have searched batlabs on this issue but get conflicting ideas.
I don't like letting my radio set in it's charger stewing away. But I would
like to pick up a radio with some assurance it has a charged battery.
I have been in a quandry about boost charging my radio's batteries.
Should you let the batteries naturaly discharge on their own or should
you give them an occasional (once a day, once every 3 days?) boost charge?
If you let them discharge on their own you chance picking up a radio
with a dead battery.
If you give them a boost charge now and then does this boost charge
qualify as a complete "charge/discharge" cycle, reducing the life of your batteries?
Let's put our heads together for some ideas.
Thanks
Dennis

[kb0nly]

For maximum life i let the batteries get run down flat by the radio before charging. I keep a couple spare batteries charged, that way, i always have one on the radio, one charged and ready, and most likely one in the charger.

You don't want to run a NiCad battery down half way then top it off over and over, before you know it that darn thing will have a memory and will only hold half a charge. Seen that a thousand times with used batteries from the local PD and FD.

If you want the maximum in user friendliness then get a smart charger and some NiMH batteries. I have yet to run into memory issues with them.

You could also get a battery charger/conditioner to finish the discharge cycle if you don't want to risk being stuck somewhere with a dead battery.

[saberjerk]

Thanks KB0nly
Some good ideas there.
HA! Gota love that Bender.
How's the weather in minnesota? I'm in montana in the middle of a blizzard. BRRRRR!!!! Try to keep your batteries warm.
Dennis

[ASTROMODAT]

Dennis, if you want a bulletproof system for ensuring optimal performance from your batteries, I would HIGHLY recommemd that you use the Motorola IMPRESS System.

Make sure to use IMPRESS batteries and IMPRESS chargers. The IMPRESS Sytem is great! The LCD on the IMPRESS charger will tell you the exact status of the battery, as each battery has a unique electronic serial number that the IMPRESS charger system reads so it custom tailors the charge "treatment" of each battery on an individual basis. This custom tailored charge treatment is based on the battery's individual performance history. It's an awesome system.

When we traded in our XTS 3000's for XTS 5000's, we upgraded 100% of our batteries and chargers to IMPRESS. Best thing we've ever done since uplifting from FM to ASTRO.

larry

[kb0nly]

Thanks KB0nly
Some good ideas there.
HA! Gota love that Bender.
How's the weather in minnesota? I'm in montana in the middle of a blizzard. BRRRRR!!!! Try to keep your batteries warm.
Dennis

Bender reminds me of a few friends, lol.

You guys out there in Montana, looks like your getting slammed with snow again? They were talking about it on the news tonight.

The weather isn't bad here, looking like below zero temps and wind chills coming up later this week. Today we had about an inch or so of wet snow, then the sun came out.

I bet you would like to see the sun about now!

I saw the Impress system at a local plant, their security force, Pinkerton, makes use of it. Nice, but i doubt i will ever be able to afford such luxuries!

Basically though, get a good quality battery conditioner/charger and your set. DON'T buy from W&W associates though, they seem to be one of the popular aftermarket charger makers. Their products are terrible, and i got the exploded battery pics to prove it. Not only that, but they wouldn't even replace the charger under warranty after it damaged my new battery. They claim that my battery was responsible, yeah right, it was a brand new OEM battery from Moto and i ordered the charger from W&W specifically to charge this battery. Even talked to them on the phone with a couple questions before ordering it.

Oh well, chalk it up to experience i guess. Now i use one from Maha. Some people don't like them for one reason or another, but i have been using them for my amateur band equipment for years so i bought a new MH-C777PLUS-II Universal LCD Charger / Analyzer / Conditioner just for charging my other radios that i work on.

One thing i really like about it is the display that shows you what it going on with the battery, voltage, capacity, etc. And they include the car kit so you can even use it as a smart charger for your radios while mobile. The clip lead that comes with it works great for charging my kids radio control stuff, the battery packs from them are NiCad. It also works slick for charging any rechargeable batteries that are odd shaped or something like that. I use it all the time to charge 9v rechargeable's for my RIB and other things around the shop. I have even used it to revive a laptop battery that was always dying to soon. I let it run a few cycles and it really did help!

[bernie]

My two bits worth:
As far as modern nicads are concerned the memory problem has been solved by the newer thin plate batteries.

In 38 years of experience with GE and Motorola 2 way radio I have made some observations about Ni Cad Batteries.

Here is how to kill one before warranty:

Allways leave it in the charger: might be down.
Be sure to leave the spares in the rack charger.
The cells swell, and leak from the seals on the positive terminal.
The electrolyte that is loose inside the battery pack causes self discharge in the battery pack, as well as corroded contacts on the battery, charging pocket, and radio housing.

Then, you can run the battery flat dead.
Turn the radio on and put it in storage.
Often the cells will short.
On occasion a jolt from a bench supply will open the shorts and the battery can be recharged.

Keep out of these extremes and the Ni Cad should last for years.
Do not deep cycle them too much, there are only so many charge cycles in a battery.

[1 Adam 12]

Look at Advance Tec chargers, they are also sold as the Motorola Conditioning charger usually with a WPN***** number.
http://www.advancetec.com/

[RKG]

This is a subject of nearly religious magnitude, in terms of the number of opinions and theories out there, the ferocity with which they are held, and people's willingness to have absolute faith in the perfect absence of evidence.

That said, my experience is that the best approach is KB's: leave Batt 1 on the radio until it beeps, keeping Batt 2 in the glovebox; when Batt 1 beeps, swap batteries and put Batt 1 on the charger. I've gotten 3-5 years of intermittent daily service out of Saber and Jedi batteries this way.

[Wowbagger]

The dreaded "memory effect" legend rears its ugly head again.

First of all: The NiCd "memory effect" happens when the batteries are used in VERY COLD environments - like spacecraft. Under normal temperatures the recrystallization of the cadnium does not occur.

NiMH don't even have that effect - no cadnium, no recrystalization.

The usual cause of reduced capacity in Ni(Cd|MH) batteries is COOKING THEM. Leaving a battery at elevated temperatures for long periods of time literally dries them out.

Many charging circuits are stupid, and continue to feed a small current into the battery even when the charge cycle is complete - that power has to go somewhere, and guess where it goes - into heating the cells.

A truly smart charger will charge the battery until it is full, then STOP ALL CURRENT until the battery voltage drops below a threshold value (due to self-discharge) and then feed a topping-up charge into the battery until it is full again, then once again STOP THE CURRENT. This will prevent heating of the battery and the subsiquent drying of the cells.

Let your charger charge the battery until it indicates full charge. Now wait an hour. Feel the battery - is it warm? If so, then the charger is either a) heating the battery because the charger itself is too warm, or b) failing to cut the current. In either case, you know to remove the battery from the charger when it is full - to keep it from being cooked.

It does not matter if you start charging the battery at 5%, 25%, or 100% of full discharge, so long as you don't cook it - charge it up, then take it out of the charger.

Most people who claim the memory effect are people who used to leave the battery in the charger all the time - then stopped leaving it in the charger when they began their regimen of "run it all the way down". It is not the "running it all the way down" that is saving the battery, but "not leaving it cooking in the charger".

[ASTROMODAT]

IMHO, the reason I like the Motorola IMPRESS system is that it constantly monitors the status (and takes into account the individual history) of each battery, and takes appropriate actions on a real time basis for each individual battery pack. Just drop it into the charger, and forget it! No need to manually have to worry about over charging, having to cycle and discharge the pack, dealing with memory effects, taking the batteries out of the charger after a certain period of time, not leaving them in the charger too long, etc. All ancient history and bad memories (no pun intended), once you convert to the IMPRESS system. All these various arguments I read here on the Batboard are automatically, continuously, and optimally handled by the smart battery software. Motorola has been very good about providing periodic firmware updates to keep everything state-of-the-art.

larry

[Will]

A while back this topic, specifically the leaving the battery in the charger, was posted and I posted some simple mods for Jedi and GP3xx, P110, P1225 chargers. I have devoloped mods for other rapid chargers as well.

Basically these and most chargers will continue to 'cook' the batteries. Astromodat is correct, the battery needs to rest.. not have any charge or tricle current until the battery falls below a specific voltage. And then only a 'bump' charge.

I have had real good success in the 30+ years by reducing the trickle charge current to a reasonable level. I don't want to remember how many HT220 rack rapid rate chargers I modified in the field, but the good side of this is how many batteries were saved.

The /\/\ sales department did not like me!

[1 Adam 12]

[quote="Wowbagger"]

A truly smart charger will charge the battery until it is full, then STOP ALL CURRENT until the battery voltage drops below a threshold value (due to self-discharge) and then feed a topping-up charge into the battery until it is full again, then once again STOP THE CURRENT. This will prevent heating of the battery and the subsiquent drying of the cells.

Hence why the Advance Tec series seems to do quite well. The Impress series also seems to work quite well with the line of radios its designed for.... but if you must maintain standby batteries and also may have a mobile application, take a look at them. And yes the slow chargers still hold their ground. The flexibility of combing not only XTS & Saber batteries , but also our Sony video and camera batteries off the same charger is quite functional

[saberjerk]

I really appreciate everybodys postings. Really a lot of good info here.
But..... No one has answered one of my main questions.

Will this "bump up charge" or "equalization charge" or what ever you might call topping off of the batteries once in a while constitute a
CHARGE/DISCHARGE cycle? Taking one more off the supposed "1000 cycle" clock????

Dennis

[RKG]

The technical answer is "it depends" (on the depth of the discharge) but the practical answer is that "it is irrelevant." Representations about the number of cycles that a storage battery can give before becoming "worn out" are vry rough approximations, based on a whole host of factors, including (but not limited to) the depth of discharge between recharges, the temperature of the battery, the nature of the charger and the recharge curve (if any) that it employs, and one's definition of "worn out." There is no magic, precise number, and the number is not decremented by exactly one on reach recharge.

Bottom line: The max life you can get out of a battery, as affected by whatever other factors may be at work, will be achieved if you run it 'til and radio beeps and then (but not before then) recharge.

[ExKa|iBuR]

Generally speaking, when I charge my batteries, I let the thing start to beep first, once it's beeped two or 3 times, turn the radio off, and back on, then wait for it to start beeping again.

Then I'll throw it into a standard rapid charger, wait for the light to show green, which as explained before, is 80%...then I leave it on for another hour and a half or so.

I've recovered many previously dead batteries using the following method:

1) Put the battery in the radio and leave it on until the radio shuts off and won't turn back on again (dead battery)
2) Drop the battery in a slow-rate charger. Forget about it for a few days (3 should do).
3) Take the battey out of the charger and plop it back into the radio, turn it on, then wait for it to beep. Then turn the radio off, and back on again, then wait for it to beep again a few times.
4) Plop it into a rapid charger until the light turns green, then wait an hour or two.

You might have to repeat this process a few times, depending on the age and state of the battery.

This has worked amazingly well for me...I've got a battery on my XTS who's date code is 721 or something like that (that's 1997), and the thing holds a faily decent charge...I had it analyzed, and it comes in at something like 75%, I've taken a battery that was previous analyzed at 80% and managed to bring it up to around 96%.

I wouldn't be using this on any mission-critical batteries, but certainly if you are a ham or a hobbyist trying to get "Something for nothing", then I'd certainly recommend you try it...you've got nothing to loose except an already dead battery

-M

[nmfire10]

It's really easy for me.

"Hey Lt, I'm running low on batteries in the back."

"How many do you need matt?"

"5 should do."

"Ok. Here's a PO, order 20."

[EKLB]

Hey ExKaliBur = Do you intend to post the tracking number and ETA for the Radius Black DTMF mikes you promised more than once to mail ?

Check the feed back forum under ExKaliBur = No Way/Waste of time if anyone is wondering about whats going on here.

If your just going to screw me off for the 4th time just say so .

EKLB