BCD396XT Battery life

[bear780ks]

So the Imedion's would possibly be the better choice since they have a lower number KB or as they say hold 85% of there capacity?

The numbers and ratings on these batteries can get confusing the thing i want the most is the longest scanning time i can get out of the battery course i know the more the scanner scans the more the pull and the more the nav light's comes on the more it drains the batteries as well i have changed the how much the lights come on..

And when pulling the batteries down i go till the scanner emits the beep and then shuts off then i pull the bats. The set i'm pulling here in a few min. went 14 hrs off the charge if i could get 20 i'd be stoked.. b

[kbehning]

Low Self Discharge cells like the Imedions, eneloops and eneloop XX don't have as high of an internal leak rate that discharges the cells regardless of if they're being used in the scanner or sitting on the shelf waiting to be used.

Think of it as a bunch of mice on a potato chip truck. The truck was stuffed full of potato chips, but there were 100 mice that are on the truck too, and they are eating the chips before they even get delivered to the people who are supposed to eat them.

Now for a low self dicharge cell, think of there only being 5 or 10 mice on the truck consuming the chips, as opposed to the 100. The truck is going to be full of chips longer.

Regular NiMH cells have a higher internal discharge rate that wastes some of the usable charge between the time it is removed from the charger to when it is used in the device. The discharge still continues once in the device, but the power consumption of the scanner is so much higher than the self discharge, it is relatively negligable. Regular cells will lose a pretty significant percentage of their charge capacity in a week or two.

Low Self Discharge cells don't consume their charge internally nearly as fast as the regular cells. They are effectively shelf stable for a year or more, losing only 25% of their capacity over that period.

For us with scanners, where we cycle a couple sets of cells between the charger and the scanner, there's usually always a full set in the charger ready to go so we take them out of the charger and put them in the scanner and away we go with a full set, getting the full use of the cells over the next 12 hours or so. In that scenario, we're not losing much at all to self discharge and you're basically best suited to look at straight cell capacity at that point.

Your 2700 Powerex cells are not low self discharge, but you're likely pulling them directly from the charger to the scanner, so they're not getting a chance to lose their charge and you get the benefit of the larger 2700 maH rating.

That's why when you're trying to get the longest runtime possible its important to really charge and discharge the cells as gently as possible so you don't lose that extra runtime due to heat exposure. Rather, your cells will naturally lose capacity over the number of cycles they're used for. 500 to 1000 cycles is generally when the cells are going to be providing only 50-75% of their original capacity. No need to rush that natural outcome along sooner by using fast charge/discharge rates.

[bear780ks]

Hey i'll go with that KB and i'm going to see if i can charge my Corun's in my new charger i'm going to at least try! Using the slow rate but i'm also going to get me a pack of those Imedions... this scanner will have the juice when it needs it

[novascotian]

I have a new charger and Immedions on the way but before I use them I have a couple of questions re the 396XT. Yes I plan to charge outside the scanner in the new charger but lets say I put the charged batteries in for portable use but much of the time plug it in for fixed use (as in why actually use the batteries if I don't need to). So if I put the switch to non-rechargeable batteries and plug in will the radio be powered off the wall wart and the batteries are entirely bypassed, and neither being charged or being used up?

Also, at the moment I am still charging in the scanner. When I charge and it says charge complete but then uplug and use it for a short while on battery, but then come back to a fixed spot and plug in again, does it do the whole charge again?... the way I am reading it here it is based on time alone, starting when plugged in?? comments??

[davidmc36]

If you remove power and then reconnect it starts the charge timer from the beginning again.

When you have the switch in alkaline setting the batteries are totally bypassed.

[novascotian]

Okay I just got my Maha MH-C9000 last night, plus Immedions, and what someone said far back in this thread is true... it is quite a charger, perhaps beyond the immediate skills of someone like me.

My first question is, is there a area somewhere else on RR to discuss battery chargers, as I have frustrations and questions about this that are not directly related to my 396XT, so this is maybe not the place to post them.

I will say simply that my first concerns are to do with all the batteries I have lying around and how to deal with them in the charger. That is the part I would post in a more appropriate spot. I will say that in some cases and on various modes some cells are coming up with the indication "HIGH" and in the instructions it says they are no good and should be thrown away.. Everyone agree??

Secondly, re the new Immedions... they each have printed on them "Ready to Use" which I think is a sort of dumb thing as it only pertains to the moment you receive them new. Forever after it is irrelevent. But continuing, I am assuming it meant they come ready to use, that is what it is implying. so at this point I have not put them in the charger. I have put the 8 of the 16 that came with the charger straight into my ham handheld. It certainly powered up and worked fine but I hardly use it, and wanted Immedions in it so I could count on it still having power two weeks or a month from now if I need it in an emergency. Since at the moment I am not actually using that radio I know I am not doing any harm. I plan to put 3 more into the 396XT and 4 into my PRO-97 and just run them, and then worry about charging them in the new charger later. If I do so the question is, have I left out a conditioning step, an omission that will have lasting consequences?

[kbehning]

1) cells that read HIGH are pretty well cashed and you can just recycle them.

2) Ready to Use: Low Self Discharge NiMH cells generally come partially charged, about 50% or so. For brand new cells, I first put them through a discharge cycle in the c9000. Put in a cell, when the charger has flashing arrow next to a function, use down arrow to select discharger, press enter, then use arrows to select a discharger rate - anything below 0.5 C is fine, but slower is better for the cell's long term health, so I'd just go with 500 mA. press enter and the discharge will start with the first cell. You can then repeat this process to put in 3 more cells to discharge.

After the discharge completes remove the cells. I then do a "cycle" function whcih will charge, discharge and then charge the cells. At the end of all that they'll be fully charged and ready for use. At the end the value listed on the display will be the capacity that each cell demonstrated during the discharge part of the cycle.

I like to start the whole process with a standalone discharge process because the cycle process starts with a charge, and I don't like putting unknown charge state cells into a charge function unless I know for certain that they're low enough to accept it and give an exit signal to the charger. I said the LSD cells generally ship with a half charge but you never know when that might change so the first thing I do is a discharge before a charge.

3) on the subject of the ham transceiver, I would not store cells in them because most ham HT's have a small background current draw in OFF that will eventually overdischarge the cells. If you take a NiMH cell too low, somewhere under 0.9V, it is detrimental to its long term health, so it is to be avoided. Just beware that you don't want to keep your cells installed in a device long term that can overdischarge them. Store the cells next to the radio, not installed in the radio - always a best bet.

[novascotian]

Thanks kbehning for your comments... I will do as you say with my new Immedions...

I would like to continue to discuss the use of the Maha charger here on RR but not sure where to go... I am thinking that the Radio Reference tavern in the Electronics section but not really sure.. Can't see anywhere else to go. I have a few questions still. The instructions are okay but I need something like the easy to read manual for my 396XT or someone to help me actually get this thing working.

[kbehning]

where ever you start your thread, just link to it from here and I'll take a look at your questions.

[novascotian]

Thanks... I will eventually go over to the Tavern area, but for now I am taking the time to discharge and cycle my 16 new Immedions as suggested, so that is going to take a while.. after that I will work on my previous batteries and that is where the questions will come.

[bear780ks]

Originally Posted by novascotian

Thanks kbehning for your comments... I will do as you say with my new Immedions...

I would like to continue to discuss the use of the Maha charger here on RR but not sure where to go... I am thinking that the Radio Reference tavern in the Electronics section but not really sure.. Can't see anywhere else to go. I have a few questions still. The instructions are okay but I need something like the easy to read manual for my 396XT or someone to help me actually get this thing working.

Nov just Go up to Forums: then tap to bring up Forums Home and then from there you can scroll all the way down into the Forums Lounge Area in there is places that talk about our everyday things and that would be a good place to Start.. Ra



Update: i see that you seen this so you may disregard my post.. if you want to

[hertzian]

Originally Posted by novascotian

My first question is, is there a area somewhere else on RR to discuss battery chargers, as I have frustrations and questions about this that are not directly related to my 396XT, so this is maybe not the place to post them.

To avoid a lot of duplication, perhaps the best place is to start with this *still active* thread of the C9000 on CandlePower Forums.

Improved Maha C9000…

While everyone is a valued contributor, especially pay heed to moderator SilverFox. Since the thread started in 2007, you may want to read it backwards.

By all means read this support / faq as well:
http://www.candlepowerforums.com/vb/...ORT-FAQ-Thread

RR is great - no doubt about it - but if you want to get down to the nitty gritty of ALL chargers out there, and pros/cons of the various manufacturers batteries, along with actual user-data measurements and charts, this is the place to go.

[bear780ks]

Yea when i took a look and when to 1 it showed 2009 and that is a thread that dates back a bit on the Verizon forums some go back to 2010 and rarely anything later than that and if a contributor stumbles on it and writes a post to it).

It won't stay open very long after that.. Ra

[doctordialtone]

Originally Posted by bear780ks

Yea when i took a look and when to 1 it showed 2009 and that is a thread that dates back a bit on the Verizon forums some go back to 2010 and rarely anything later than that and if a contributor stumbles on it and writes a post to it).

It won't stay open very long after that.. Ra

Thank you. I believe that you have crystallized all of our thoughts eloquently. When it comes to meaningful information, sometimes less is more. What was the topic?
>Smiley Faces Omitted<

Read kbehning's advice.

[bear780ks]

Well good info any way you can get is always better than non at all Doc. and yes threads do sometimes tend to loo into places they should not).

I have seen threads on the Verizon Forum on stuff that didn't mean hell a beans linger on for months on end and the Moderator's have to finally close them for one-> the trash talking which can get very Nasty!

But for the info that does come here on forum my hope is that it helps the individual or individual's that needs it the most.. Ra


I wanted to Add i was able to charge the Original Corun batteries that came with the scanner in my new charger on Soft charge with NO issues at all and as for them getting warm they did just slightly at the touch..

[eorange]

Originally Posted by hertzian

Tip: To actually test the capacity of a previously fully charged battery, one uses the manufacturer-standard C/20 rate for DISCHARGE. Ie, for a 2000mah cell, after you insert it, you would manually select "discharge", (up/down button) and then "enter", and then specify a 100mah discharge rate the same way. When the 9000 says "done", it will also show you how many milliamps it discharged, revealing the true capacity of the battery.

That's a really good tip. I haven't done anything but "charge" with my C9000, and I've always wondered about that.

[hertzian]

Yes, using the 9000 to discharge at the C/20 rate and noting how much capacity it reports is nice by itself. But you can also use it to test *other* chargers, such as the one inside the Uniden!

Start from a cell that has been through a few cycles, and let it charge fully on the 9000. Run the C/20 rate on it and note the capacity. Now place it inside another charger, and let it fully charge in that unit. Pull the cell, place it into the Maha, and run the C/20 discharge test again. This will let you know if the other charger has really done the job.

It is also the way to test individual cell capacity for inclusion into a "pack" which you try to keep together. Ie, you buy a pack of 4 new cells for your 396, which only uses 3 at a time. After running 2 or 3 cycles on them if they are brand new, do the C/20 discharge test, and put the 3 cells that are closest to each other in capacity into a "pack". Save the odd man out for possible inclusion into another device or pack.

Most cells should be recycled or repurposed into other low-demand non-critical devices when they reach about 80% of their original capacity. For example, with a 2000 mah battery, if you later test it with the C/20 discharge, and find that it only has about 1600mah of tested capacity left, consider replacing the *entire pack* with a new set.

Self-discharge test: Bought some standard 2700mah super-zappo brand off ebay? After 2 or 3 break-in cycles if new, run the C/20 discharge (135ma, but you may have to decide to run either 100 or 200 mah on the mah - I'd go with 100 in this case) and note the capacity. Charge it back up fully. Let it sit for a week or two, and run the C/20 discharge test again. Let it sit for a month and test it.

[bear780ks]

Hey KB check it out i went and got me one of these little Guys and Soon i will have a pack or two of some Eneloops to Go into it. I might need some more tips from ya but i found your Post at what you need to set the Batteries to Charge.. Have a good weekend and Happy Easter

[hertzian]

Originally Posted by novascotian

I will say that in some cases and on various modes some cells are coming up with the indication "HIGH" and in the instructions it says they are no good and should be thrown away.. Everyone agree??

Yes - they are more of a resistor than a battery at this point. As such, they have much less capacity than normal, heat up much faster when charging, and discharge quickly. Trust the 9000 on this. Some like to fool the charger or use them in super dumb trickle chargers to get some life back into these zombie-cells, but they are really a waste of time, and a danger if charged inside the radio.

When the 9000 first starts, if it does not immediately show a HIGH condition, the very first data it shows you, and shows it to you *only once* upon cell insertion is the measured impedance. Here's a quick detail of that data:

1.60 = very fresh cell
1.80 = middle aged
2.00 = old aged
HIGH = toss them

After this data is shown after insertion, the display will actually read out the battery voltage for the rest of the charge cycle.

Re: "pre-charge". It is an acronym for low-self-discharge. It does NOT mean that you should just toss them in a drawer for an emergency later. It only means that when you purchase them, you'll get SOME life out of it, but since they are only about 50% charged at the factory, the smart thing to do is immediately charge them when you can.

[bear780ks]

Hertzian can i give you some Reading from when i charged my Coruns if your not to Busy?