NiMH Batteries

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Patch42

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I have a bunch of alleged 2700mAH NiMH batteries I purchased a while ago from a place I've dealt with many times before. In the past I've always been happy with the batteries from this place. They're inexpensive and worked very well.

This new batch, however, has been a huge disappointment. The coverings, which actually provide electrical insulation for the case, are extremely thin, brittle, and several of them have split or cracked, exposing the metal case of the battery and presenting the danger of shorting. Even worse, the capacities I'm seeing are not remotely close to the 2700mAH that's advertised. I know most batteries advertise "total capacity", some portion of which can never, in practice, be used. But with most of these batteries, according to my MH-C9000, I'm seeing capacities well under 2000mAH.

I just put a brand new set through the "break-in" charge cycle and the charger is telling me the capacity is about 1800mAH. I realize that may increase a bit over time, but that's the kind of numbers I'm seeing on most of them. I'm getting tired of changing batteries twice a day in my scanner.

Does anyone know of a battery that actually lives up to its capacity claims? I'm not saying a 2700mAH has to go to 2700, but 2300-2400 would be nice. This getting only two-thirds of the rated capacity is getting very old.
 

Grog

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Buy quality, and buy it once.

Eneloops have actually been checked to be more than the 2000mah they are are rated. While you won't get 2700, you will get what they say you should be getting.
 

iMONITOR

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There has been numerous threads on this topic before. It seems the higher capacity batteries, and/or the fastest chargers are the most problematic.

I've been using Radio Shack's Cat No 23-1302, 2-hour charger. It comes with four "AA" 2100mAh NiMH rechargeable batteries. The charge last long, and the batteries re-charge over, and over, and over. I've had no problems, very satisfied. It's only $19.95 including four batteries.
 

unitcharlie

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Hi Patch... A friend recommended Sanyo eneloops after I complained that my "famous brand" 2650 mAh rechargeables were trash after six months in service.... I need batteries that last because I depend upon my scanners to put shoes on the kid's feet.... I get between 10 and 12 hours in my PRO 96 with the light on most of the night and a lot of freqs in the working and VScanner memories... I keep a spare set for the trade-out when they die... I don't abuse them, but they take a lot of punishment because the sets in the two radios I carry on my person go where I go and are in the wx, etc.... I charge them in the radio and in a charger (ironically, the charger is the one "famous brand" customer service told me I needed to charge their 2650 mAh batteries).... as my other batteries die they are being replaced with the eneloops...
 

Patch42

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There has been numerous threads on this topic before. It seems the higher capacity batteries, and/or the fastest chargers are the most problematic.
I did a search last week and the latest thread I could find was from about a year ago. Maybe I searched for the wrong thing.

The charger I have lets me set the charge rate. I've used several rates between 200mA and 1000mA. Generally I use 500mA as a compromise setting. The charge rate doesn't seem to have an impact on the effective capacity.

I appreciate the various recommendations for the Eneloop batteries. Unfortunately, the capacity of those, while quoted honestly, seems to be little more than the batteries I already have. As far as pure capacity is concerned, it seems I'm best off using what I have until they wear out. At that point I will probably take a hard look at the Eneloops.

I'm breaking in a new set of the existing batteries now. With these I'm going to put them through at least three full break-in cycles to see if that makes any difference.
 

pdfdems286

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for whatever it's worth i've been preliminarily pretty happy with my delkin 2900 mah aa batteries.
they run my psr-500 for about 12 hour's straight.this is with all conventional channel's,and a police frequency that hardly ever shut's up.i also got a bunch of the sanyo eneloops for low discharge.i bought them all from thomas distributing.price's are fair,they give discount's,something alway's get's thrown in for free.
 

PFCCooper

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I have three sets of Rayovac Hybrid rechargeable battery's that are 2100 mAh NiMH and they last in my BC246T anywhere from 16 to 19 hours but the only place I am able to find them are at Target. my first set came with two AA's and two AAA's and a charger.
 

gmclam

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Charging NiMH batteries

What I'd like to know is not the brand or capacity of batteries people are using per se; but HOW are they being charged. How many people charge them in their scanners? How many use an external charger, and which one do they use?

I started a thread a month ago regarding my experience with several brands of batteries and the Maha PowerEx C-9000 charger. They've sent me a new charger (no difference); I've sent them a sample of each of my "bad" batteries (some were still in an unopened package); and they are now sending me some of their batteries to test. I have several issues with the charger which have not yet been addressed.

Bottom line for now is that I actually have better luck with batteries being charged in the scanner. If they're getting HOT (not just warm) when charging, they are "bad" anyway. I've had some good 2500 mah brands/models of batteries, and I've had some horrible brands/models. Energizer & DuraCell are the worst. Panasonic (2300 mah) & Rechargeable (solid blue in color) are on the top of the list.
 

Grog

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What I'd like to know is not the brand or capacity of batteries people are using per se; but HOW are they being charged. How many people charge them in their scanners? How many use an external charger, and which one do they use?

I have never charged a battery in a scanner, just do not want to risk something going wrong and having a messed up scanner. That being said, I also have quite a few rechargeable batteries around (120 eneloop, plus about 20 of other brands) so that I am never without a spare set ready to toss in the scanner.
 

enine

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I switched to eneloops early in 2006, charging in a maha c401fs at the time and now a c9000, they really do work. the problem with the higher capacity batteries is the insulation layers have to be thinner so they self discharge faster and are prone to damage from heat, drops, etc. My eneloops outlive any higher capacity batteries in real world testing, they even match lithiums in performance.
 

Patch42

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What I'd like to know is not the brand or capacity of batteries people are using per se; but HOW are they being charged. How many people charge them in their scanners? How many use an external charger, and which one do they use?
I have charged the batteries in the scanner, but do not do so as a habit. I generally use the Maha C9000. It seems to work okay, though, since I'm not happy with the capacities it's displaying, there is a possibility the charger is at fault.

I have a couple sets of batteries I got a few years ago that the C9000 refuses to charge. These batteries have an odd voltage curve, showing very high voltage at first and then dropping to a more normal voltage. Most of the time the C9000 produces a "HIGH" error and stops charging them. Sometimes if I keep putting the batteries back in and restarting the cycle three or four times they'll start with a lower voltage and then go through a normal charge. I've tried high charge rate, low charge rate, no difference.

I also have a Maha 401(something) I've had for several years. It charges these same batteries without any problem.

In the course of my investigation into battery brands and capacities, I came across an article written a couple years ago concerning batteries for digital cameras. The author said his research showed it was quite difficult to get a battery fully charged. He couldn't find a single charger that would put the maximum amount of energy into the batteries. Eventually he settled on a method of using a smart "fast" charger first and then putting the batteries in a dumb slow charger overnight to top them off. He said this always got the batteries up to maximum charge.
 

Patch42

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I thought I'd post an update on my battery saga. After another incident of almost catching my pants on fire from a shorted battery in my pocket getting incredibly hot, I decided I needed to do something (aside from taking the batteries out of my pocket).

I ordered some Ansmann 2850mAh batteries from Thomas Distributing. No particular reason to pick this brand other than I've heard good things in the past about Ansmann 9V rechargeables.

The batteries arrived last Thursday and I immediately put a set through the "break-in" cycle on my Maha C9000 charger. Initial capacities reported by the charger varied, but were all above 2600mAh. (The cheap batteries these are replacing are rated at 2600mAh -- I mistakenly said 2700 in the original post -- and typically show a usable capacity of about 1800mAh.) So, right out of the gate the Ansmann batteries are looking better than the el-cheapo ones.

I ran the PSR-500 off these batteries off and on over the weekend. I didn't precisely measure the time, but my guess is that they lasted at least ten hours. I was initially monitoring with the scanner hooked up to the computer and could see the voltage level reported by the scanner. It was surprising to see a voltage above the nominal 1.25V (5.00V total) after a couple hours of use.

I ran them to scanner shutdown and did a "discharge" cycle in the charger to see how close to fully depleted the PSR-500 got them. Two of them stopped discharging immediately, showing 0mAh used. The other two both showed less than 35mAh to full depletion. The PSR-500 looks to get most every last usable electron out of the batteries before giving up.

The batteries were then put through a normal charge cycle at a rate of 500mA. The charger reported all of the batteries taking over 2800mAh to reach full charge, with one of them going over 2900mAh. This seems to bode well for these batteries being honestly rated and powering the scanner for at least a full working day. While the rated capacity of these new batteries is only 10% more than the rated capacity of the el-cheapo batteries, the actual capacity seems to be more than 50% greater.

It seems, Grog, you were right. Buy quality and buy it once.

I emailed the "other" company about the problems I've had with their batteries. It's been a week since my email and I've yet to get a response. Not that this surprises me.
 

rico47635

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I have a bunch of alleged 2700mAH NiMH batteries I purchased a while ago from a place I've dealt with many times before. In the past I've always been happy with the batteries from this place. They're inexpensive and worked very well.

This new batch, however, has been a huge disappointment. The coverings, which actually provide electrical insulation for the case, are extremely thin, brittle, and several of them have split or cracked, exposing the metal case of the battery and presenting the danger of shorting. Even worse, the capacities I'm seeing are not remotely close to the 2700mAH that's advertised. I know most batteries advertise "total capacity", some portion of which can never, in practice, be used. But with most of these batteries, according to my MH-C9000, I'm seeing capacities well under 2000mAH.

I just put a brand new set through the "break-in" charge cycle and the charger is telling me the capacity is about 1800mAH. I realize that may increase a bit over time, but that's the kind of numbers I'm seeing on most of them. I'm getting tired of changing batteries twice a day in my scanner.

Does anyone know of a battery that actually lives up to its capacity claims? I'm not saying a 2700mAH has to go to 2700, but 2300-2400 would be nice. This getting only two-thirds of the rated capacity is getting very old.
My experience with those rechargeable batteries in scanners is that they aren't very good. The main problem I have had is that alkaline batteries are normally rated at 1.5 volts and the NiMH batteries are rated at 1.2 volts. My scanner requires 6 batteries, for a total of 9 volts. When I use the MiMH batteries, I hit the ground with less voltage than the scanner requires for operation, so there isn't any room for the voltage drop that is normal with using any batteries. I found that I was constantly recharging batteries that really weren't discharged in the first place. They just didn't have enough voltage in them to run the scanner anymore because they started off being .3 volts lower than what an alkaline battery would be. I went to Radio Shack and bought a 9 volt power supply for $20 and haven't had a problem since. My suggestion would be to save your money and get one of these. Otherwise, you are going to spend a lot of money on NiMH batteries. Of course, none of this matters if you always use your scanner away from home all the time.

The NiMH batteries work much better in my handheld ham radio because it's designed to operate on 7.2 volts.
 
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N1SQB

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Maha MHC-801D smart charger!

Thats my choice and I'm sticking with it.....LOL I use this charger to charge my over the counter Duracell 2650 Mah and my Sanyo 2700 Mah NiMH batteries. I have a total of about 30 batteries in constant use. Not a single problem ever with any of my batteries since I began using this charger a year ago. I can see each cells' individual charging process. I soft charge/condition them at least twice a month. That is what makes a difference. People for the most part just know about charging and recharging batteries. Most dont think about slow charging or better yet, conditioning their batteries . This process charges,discharges and recharges the batteries which restores them for better / longer performance. I used to think this was a load of advertizing bull until I actualy upgraded my charger to one that does this. I swear by this process.

Manny
 

rico47635

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Thats my choice and I'm sticking with it.....LOL I use this charger to charge my over the counter Duracell 2650 Mah and my Sanyo 2700 Mah NiMH batteries. I have a total of about 30 batteries in constant use. Not a single problem ever with any of my batteries since I began using this charger a year ago. I can see each cells' individual charging process. I soft charge/condition them at least twice a month. That is what makes a difference. People for the most part just know about charging and recharging batteries. Most dont think about slow charging or better yet, conditioning their batteries . This process charges,discharges and recharges the batteries which restores them for better / longer performance. I used to think this was a load of advertizing bull until I actualy upgraded my charger to one that does this. I swear by this process.

Manny
Well, to each his own, Manny. I don't take my scanner anywhere out of my house, so it doesn't make sense for me to run it with using batteries and chargers. The nine volt power supply does the trick for me. I do, however, use rechargable batteries in my handheld ham radio. For now I use the original battery pack my HT came with, a higher capacity pack I bought, and the battery case I use the AAs in. I rotate them and haven't had any problems thus far. I have problems justifying the expenditure for one of those single circuit chargers, seeing as how I am only using 6 batteries on a very part time basis. I can see how someone who uses a lot of these AA rechagables would benefit from having one.
 

City_Seven

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Does anybody know where I can pick up some sanyo eneloops in the Vancouver BC area?
 
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CCHLLM

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The simple answer as to why some work well and live up to their "ratings" and others don't is that there is no one simple answer. All cells are not created equal, and the larger the difference between the charge and discharge rates of one cell and the next when paired up in a battery, the worse the performance of the two together will be on both discharge and charge operation.

Quality cells are inspected and tested and "matched" to a performance standard. Therefore, they perform better when ganged up to make a battery because they all charge and discharge equally. A cell with more internal resistance will create more heat during recharge, and will take longer to recharge and will discharge faster because of its own greater internal resistance. You can sometimes spot the bad ones by feeling the cells for temps as they charge. The ones with higher resistance will get warmer during the cycle.

The good cells won't get full charges because of the poor charge rates (higher resistance) of the bad cells, which in turn, inhibits the recharge rates of the good cells and so on. The poor cells,, having less of a charge, will speed up the discharge rates of the good cells because the good cells end up carrying most of the performance load trying to power the equipment and help overcome the higher resistance of the poor cells.

Bottom line: when you put AA or AAA cells in your device, the battery holder/compartment wiring connects them together and makes a battery. If the cells aren't pretty closely matched, the performance is immediately compromised and goes downhill. How fast that happens depends entirely on how you charge and discharge the battery. Proper charging and discharging cycles will help even the most mismatched sets of cells to a certain point, but nothing will correct the effects of crappy cheap, mismatched, or defective cells.
 
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rico47635

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The simple answer as to why some work well and live up to their "ratings" and others don't is that there is no one simple answer. All cells are not created equal, and the larger the difference between the charge and discharge rates of one cell and the next when paired up in a battery, the worse the performance of the two together will be on both discharge and charge operation.

Quality cells are inspected and tested and "matched" to a performance standard. Therefore, they perform better when ganged up to make a battery because they all charge and discharge equally. A cell with more internal resistance will create more heat during recharge, and will take longer to recharge and will discharge faster because of its own greater internal resistance. You can sometimes spot the bad ones by feeling the cells for temps as they charge. The ones with higher resistance will get warmer during the cycle.

The good cells won't get full charges because of the poor charge rates (higher resistance) of the bad cells, which in turn, inhibits the recharge rates of the good cells and so on. The poor cells,, having less of a charge, will speed up the discharge rates of the good cells because the good cells end up carrying most of the performance load trying to power the equipment and help overcome the higher resistance of the poor cells.

Bottom line: when you put AA or AAA cells in your device, the battery holder/compartment wiring connects them together and makes a battery. If the cells aren't pretty closely matched, the performance is immediately compromised and goes downhill. How fast that happens depends entirely on how you charge and discharge the battery. Proper charging and discharging cycles will help even the most mismatched sets of cells to a certain point, but nothing will correct the effects of crappy cheap, mismatched, or defective cells.
So, basically what you are saying is to make sure all the batteries are the same brand with the rated MAH, or it will cause problems.
 
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