9v battery and charger recommendation needed for wireless mic transmitter

[Grayson73]

Hi,

We use 9V batteries for our wireless microphone transmitter. There is nothing more annoying than the microphone cutting in an out due to the Duracell alkaline running out. Is there a consensus on some good 9V rechargeables and charger?

Also, the casing needs to be standard size. We tried some rechargeable batteries and the casing was too large for the transmitter.

Thanks,
Grayson

 

[VidPro]

Re: 9v battery and charger recommendation needed

get a duel diversity UHF microphone system that uses AAs , and change it more often, like every 5 hours of actual use.
only question then is how are you going to pay for it

there are some changes from the last time i tried them, but the results are always dismal. or the cell doesnt fit. or the voltage issues

batteryjunction has a good selection of nimh. worth looking at.

ultralast lithiums are said to have some 1200 ma, regulars good alkies have some 550ma and the bestus ni-mhy now have about 250-330 , which is better than the old 180, which was useless, now that doesnt speak of the drain which is important in small cells items.

http://www.powerstream.com/9V-Alkaline-tests.htm

got $5-7 each for ultralast and some of them didnt do well at all, for some reason, and some did great, but they too are boxy and harder to fit, but at least they do fit. that might get you 2x runtime, many xXx cost more.

i tried the new 400ma li-ion, which i Knew already was a max voltage of 8.4 and it was terrible sized , not to mention that most devices want more voltage than that for sure.

then there is a new Li-Fe-Po which should come out to be a better "match" for the voltage, but more dismal capacity again.

if i was going to try one more rechargable, i think giving the 9.6v 250ma ni-mh would be interesting, just depends competly on the device.

more bad math:
assume for a second that were getting some:
400ma from a alkie, before the voltage is to low and its in the midrange of 8v for its operation, that is some 3.2Watts of power ? isnt it
with a lithium $$$ cell, probably get some 900ma at a midrange of more like 8.5v some 7.6w of power
with the ni-mhy 8.4v type at say 330ma that is 2.8w of power.
SO
why do 9V operational devices suck so much worse than a 2xAA devices , which is say in ni-mh 1900ma x1.2v x2 = 4.6Watts

i am clipping to less digits beings these are totaly rough figures anyways, and trying to stay in the realism bounds.

 

[Beacon of Light]

Re: 9v battery and charger recommendation needed

How about the iPower Li-Ion 9v charger and 500mAh and 520mAh 9v cells? I want to order that combo but Battery Junction only sells them separately and I want the combo price other places are selling it for, but I don't want 2 separate shipping charges as there are other lights from Battery Junction I want.

 

[Grayson73]

Re: 9v battery and charger recommendation needed

Thanks for the info. What was the specific brand that fit?

If anyone has info on batteries that are almost identical to alkaline battery size, please let us know.

 

[VidPro]

Re: 9v battery and charger recommendation needed

How about the iPower Li-Ion 9v charger and 500mAh and 520mAh 9v cells? I want to order that combo but Battery Junction only sells them separately and I want the combo price other places are selling it for, but I don't want 2 separate shipping charges as there are other lights from Battery Junction I want.

Bagged instead of canned, its still the same basic thing
Lithium-Polymer material, Working voltage 8.4V~6.5V

8.4MAX voltage, ~7.4v Nominal got devices that want a 7v battery, some things WILL work just fine with it, but things i tried want a 9volt battery.
put whatever you intend to TRY and have run on this, on a power supply give it 7v and see if it runs fine, if it does then its at least worth trying, if it doesnt dont even bother, its not going to add a few volts to itself based on the wrapper on the outside

yes i am OFFENDED by the battery being labeled 9V, but what i am most offended by is the claim that it WILL work in devices, Can be used in 9v devices should be changed to it might work in SOME 9V devices. especially ones that dont have a fit as soon as the voltage drops below 8 or something, when this thing has barely begun to work.

i dont want to Rag on it, because we need all the options and possibilities we can get, but it is not any form of assistance to potential users to BS thier way through to getting this if they will be stuffed with a flamable rock.

your average 9v battery starts at more like 9.36v and they are usually low drain devices, or they wouldnt be even using a 9v to begin with, low drain high voltage. so the devices dont usually have the "alkaline" problem so much of the voltage tanking on startup.

name one HIGH drain 9V device that you have in your house?
remote - no
garage door opener - no
transister radio - medium
backup batteries in clocks - NO and if this has the protection drain, bad idea
timers - no
digital mutimeters - mabey medium, but if you got a cheap one and it fails to give correct readings with poor voltage NO
smoke alarms - hell no i aint listeining to mine BEEP one more time over a slight voltage drop
digital thermostats - no
wireless transmitter - mabey if it doesnt lose RANGE from a lower voltage.
9V emergency cell phone chargers - probably, but who would buy one that used a 9v?

 

[Sub_Umbra]

Re: 9v battery and charger recommendation needed

This is a tough subject that would seem to have at least four important variables:

• How much voltage does the mic actually need -- and does the potential secondary battery have enough cells to supply it?
• Does the battery candidate suffer from Form Factor Creep and will it even fit in your mic?
• How much of a an energy hog is your mic?
• What kind of 'shows' do you do? Are they one hour cabaret shows, sermons, etc -- are they full length plays and musicals -- or are you doing all day film shoots 'til zero-dark-thirty?

This gets complicated very quickly.

Below are a couple old threads that are very good reads on this subject:

Are there any NIMH low discharge 9 volt batteries?

9V NiMH only 7.2V?

We've not yet found secondary 9V batteries that we are ready to jump into, although we have saved a bundle by running many of our mics on NiCD AAs for live performances and rehearsals. We're still buying Procells in bulk for the 9V mics.

 

[Beacon of Light]

Re: 9v battery and charger recommendation needed

hehe, I started that thread (first link of yours) Subumbra. Still waiting for a decent review of a low self discharge 9v.

 

[Grayson73]

We use them for 3 hours at a time for speaking.

I found a thread here regarding this topic:

http://www.churchmedia.net/general-audio/27619-rechargeable-9-volt-batteries.html

 

[VidPro]

We use them for 3 hours at a time for speaking.

I found a thread here regarding this topic:

http://www.churchmedia.net/general-audio/27619-rechargeable-9-volt-batteries.html

"We purchased 20 Maha brand 9.6volt rechargables and they lasted about 8 months :duh2:"

and you can figure out why quick enough, SERIES charging, and reverse discharge, and bad charger alogrythms for charging , balancing and all, its not like you can get the cells out and charge them individually

if a person was to use ni-mhy (preferably some magic LSD ) they would want to Pull early instead of rundown, and have a perfect charging alogrythm that purposfully included very slow topping to balance the cells. because its 3+ hour type discharges , i would probably slow charge them Only, it not like they need to race cars with them.

"Discharge them completely before recharging."
no please dont, how can you discharge them when they are stuck in series , without causing a reverse charge, discharge to some set voltage? NOOO, because a few cells in it could still be high, and one could still be already at 0v

the li-ion and li-poly and li-fe-po solve some of the excessive seires issues, but i bet that not one of them still has proper balancing, and from my limited electrical knowledge, i think they can put "cutoff and continue" balancing in protection for just a few more quarters than they already spent. the lith chemestries would have the great Low self discharge, and the li-fe-po is higher in voltage and "safer" if you can cope with less total capacity/runtime.

 

[Matt7337]

I do sound tech at a local church which recently had a whole new audio and visual system installed... All the mics and bodypack transmitters are Sennheiser equipment. We use Duracell PP3 batteries in all the cordless mics and they seem to last just fine... probably about 5 or 6 full one hour services before they flash a low battery indicator. The Senn Monitor up at the desk has a battery indicator on it so we always know when it needs a new battery before a service anyway.

I might switch them over to rcr's if thee are any good suggestions on what to use here... after all we are running a lot of high quality mics and transmitters, we may as well have a decent power source in them which would save a little on PP3's

 

[VidPro]

do you think mabey mdocod could make us some 6x AAAA adapters then source some enloop Quad-A's on a group buy from AW, and then send them off to 4sevens to be fluted and annodised. then we just send the transmitters into mod-a-mag for boring .
then if we can get mrAl and silverfox to colaberate on a charger, put in a few tritium vials so they can be found easily, i figure for $6 or $7 hundred each, we could get a real setup going.. mabey get one of the dealers to list it permanentally. so who wants thiers in Titatanium?

 

[SilverFox]

Hello Grayson,

The biggest problem with NiMh 9V batteries is that most of them have been sitting on the shelf for an extended period of time. This leaves the cells in the battery self discharged and badly out of shape.

If you are willing to put some effort into reviving the batteries before use, you can get decent life from them, but I would not classify them as "plug and play." The main issue has to do with the chargers. A lot of them do a low current charge for a set amount of time. If the cells are not balanced in that amount of time, you end up with an imbalanced condition and very poor performance. Once you get the batteries in shape, the chargers see to do OK.

The iPower brand has consistently been crap, so I would suggest staying away from that brand. You may get a couple of them to work, but it seems that you end up going through 2 - 3 to get those couple that work.

If size is important, you need to stay away from the 9.6 volt batteries. They are bigger and don't always fit into tight battery spaces.

I have been using the Titanium 9V 260 mAh batteries, and once I got them into shape, they have been performing very well. Getting them into shape involved some advanced conditioning, and the use of my Schulze charger. Once I got them into shape, the standard 9V charger seems to do a good job, but most of them don't go to a high enough voltage to charge the 9.6 V batteries.

Once I get caught up on all my other testing, I am planning on doing a review of the Titanium 9.6 and 8.4 volt batteries. I have a few months using them behind me now, so it is time to see how well they are holding up.

If 9 volt batteries had a manufacturing date on them, and if you could find some that were only around a year old or so, you wouldn't have to go through all of this, but that is very difficult to do.

Tom

 

[Grayson73]

The intriguing thing about the iPower battery is that it is Lithium Polymer and it's 500mah or 520mah. That is twice the capacity of the NiMH batteries.

http://ipowerus.com/

 

[SilverFox]

Hello Grayson,

Please excuse me for not being more specific...

The iPower 9V batteries I was referring to were NiMh chemistry.

I have not looked at the Li-Po versions of 9V batteries, but VidPro tried one and found its size to be larger than regular 9V batteries.

Tom

 

[VidPro]

Hello Grayson,

Please excuse me for not being more specific...

The iPower 9V batteries I was referring to were NiMh chemistry.

I have not looked at the Li-Po versions of 9V batteries, but VidPro tried one and found its size to be larger than regular 9V batteries.

Tom

and i found it to be (what i expected) very low in voltage, its just 2X3.6v cells in series with 2x series protection.

the li-po version does look smaller, but i suspect some of the same lower voltage issues, where a lot of devices would prefer the ni-mh versions.

 

[Beacon of Light]

SilverFox, have you tried the iPower 9v NiMH, NiCd, Li-ion charger? I just bought one and I wonder how different it is to either of the 2 Ray-O-Vac chargers I have. Seemed to charge 2 questionable Ray-O-Vac NiMH 9v cells ok with no problems, that had a hard time even registering on the Ray-O-Vacs.

 

[SilverFox]

Hello Beacon of Light,

I have no experience with the iPower charger.

Tom

 

[Grayson73]

We started using them this past Sunday. We have 4 of the 520mah li-po 9v batteries and we will be using them once a week.

A few questions:

1. Should we use the same one each week or rotate the 4 so that we use each once during every 4 week span?

2. Should we leave the batteries on the charger or remove them after they are fully charged?

3. Is it ok to charge the battery that we use each week even though the battery might only be 50% used?

 

[VidPro]

1. Should we use the same one each week or rotate the 4 so that we use each once during every 4 week span?

if you only need one and a backup, you shouldnt have even bought the other 2 li-ion (type) chemestries dont last as many Years as other stuff.

you could use all 4, or you could discharge 2 of them to 50% capacity (not voltage) and store in a cool safe place, then they will last longer.
at any rate they are only going to be good for 2-3years MAX, unless they put high quality cells in, i doubt that. use it or loose it, or just store it really well.

2. Should we leave the batteries on the charger or remove them after they are fully charged?

never trust a charger, any charger, especially in some empty building or something. the battery should be treated like a Small version of a RC (radio control) pack. you could check the chargers specs and the battery protection, and you could indeed leave it on once your SURE of it, but you still wouldnt trust a charger, even knowing its specs and termination.

3. Is it ok to charge the battery that we use each week even though the battery might only be 50% used?

its series, and its not balancable, your better off not trying to deep discharge it. and recharge it before its fully depleated, if you had the right stuff, you could deep discharge it every once in a while, but reality says you would actually have to have balancing taps to do so.
Bagged Li-ion is more ok with topping it off and short cycles because of its low-self discharge, it still will get voltage depression but not as fast as say ni-cd.

if it should ever start Bulging, or not fit the slot anymore and you dont know why, check for bulging, if its bulging it is getting ruined and should be treated as a fire hazzard at that point

so are they fitting in tight spaces well? how is your transmision RANGE effected?

 

[bob13bob]

was going to pick up bty 280mah on dx for $4 each, reading discussion below, and not wanting to spend $10/battery for powerex I'm going with the tenergies lsd amazon $4.5/each. I can not find any posts where someone actually tested current on them though.....

I would gambol on the bty, but them sooner rather than later. they got mixed ratings

source
http://club.dx.com/forums/Forums.dx/threadid.13328

Hi,

I've bought this battery, and I've mesured at third cycle 197mAh, under a 30mA load (charge 20mA with deltaV detection). Maybe this capacity would increase after a few cycles ? It takes several hours to cycle at such rate...

It's quite honest, to my mind ! For exemple I measured for a 9V 175mAh Energizer battery around 200mAh. Real 9V 300mAh battery exist : Powerex 300mAh are mesured around 300mAh, and Microbatt 300mAh too, but they are much more expensive !

Alcaline batteries are told to make around 500-600mAh, I haven't mesured.

My better 9V batteries are :

-Powerex 300mAh (8,4V,)mesured 300mAh
-Microbatt 300mAh (8,4V), mesured 295mAh
-Conrad 250mAh (8,4V), mesured 270mAh
-Conrad NiCd 150mAh (8,4V), mesured 235mAh (Conrad is a european distributor brand, don't know where batteries are build), probably in China
-Energizer 175mAh (8,4V), mesured 200mAh
-BTY 280mAh, mesured for the moment 197mAh
-GP170 (7,2V), mesured 190mAh
-Energizer 150mAh (8,4V), mesured 165mAh (old battery)