OT - 9 volt Batteries and Musical Devices

[Angie]

May or may not be pertinent to 9V, but over the past 4 or 5 years I have been plagued by leaky, contact corroding, made in China, Duracell AA and AAA alkaline cells. Recently a batch of Duracell AAs dated March 2028 exhibited leakage in storage even before being installed. This has led me to totally abandon the brand. I have invested in Panasonic Eneloop rechargeables. These have served satisfactorily in our church's wireless mics for approaching 10 years. Unfortunately, rechargeable 9 V is not so easy.

I was just researching this today. Seems Duracell is not the brand to buy anymore. GP Greencells seem to have a better track record in the leakage department. The GP's are zinc chloride where the Durcell is alkaline. If that matters to anyone.

[cgrafx]

I was just researching this today. Seems Duracell is not the brand to buy anymore. GP Greencells seem to have a better track record in the leakage department. The GP's are zinc chloride where the Durcell is alkaline. If that matters to anyone.

Not sure I'd bet on that leakage record. The power density and usable shelf life are also heavily in favor of alkaline chemistries.

"While an alkaline battery can last for as long as 7 years, zinc batteries can only last anywhere between 1 to 3 years before becoming unusable. The zinc casing is slowly being eaten away by the acidic electrolyte that is contained inside."


good article here: http://www.differencebetween.net/tec...-and-alkaline/

The best move is to shift to NiMH or Li-Ion which don't have the corrosive leakage issues of the Lead-Acid/Alkaline type chemistries.

[Naturally Digital]

So, here's my question. My VOM says a new Duracell puts out right on 9v. Before I lay out the cash for rechargeable batteries and a rig to charge them through, am I foolish to think that 8.4 v might be just as good as 9 v when they are all charged up?

Judging from the discharge curves, and depending what your priorities are (saving money, saving the planet, top-notch sound etc), it could still be worth setting yourself up with a NiMH kit. Maybe they won't start out with the same sparkle as the alkaline, but there's a good chance they'll sound more consistent for longer periods (flatter discharge curve).

https://data.energizer.com/pdfs/nh22-175.pdf

https://data.energizer.com/pdfs/522.pdf

https://www.duracell.com/wp-content/...604_US_CT1.pdf

If the NiMH sound good enough for everyday practicing and general use, then for special occasions maybe try the 9v lithium batteries.

https://data.energizer.com/pdfs/l522-1119.pdf

I have experience running the AA's in Lectro transmitters and they are impressive.

https://data.energizer.com/pdfs/lith...l92_appman.pdf

[Dave Labrecque]

New idea: phantom power over your guitar cord. Enough of this voltage and discharge curve tomfoolery.

Somebody—make it happen! Maybe you'll end up a millionaire in the process. But the best part is that John will have to find something new to get all curmudgeonly about. (Kidding, John. Love ya, buddy. )

[Angie]

Not sure I'd bet on that leakage record. The power density and usable shelf life are also heavily in favor of alkaline chemistries.

Just going by experience. I've noticed GP's and other zinc chloride brands shipped with TV remotes that don't exhibit signs of leakage after many years. But other alkalines do. These are AA and AAA. 9volts may have a different out come.

[Angie]

New idea: phantom power over your guitar cord. Enough of this voltage and discharge curve tomfoolery

That would be scary. I encounter enough guitar players who don't know enough about their own instrument to know that there is a battery in there! I can't imagine how many guitar electronics would get damaged from lack of information.

[John Ludlow]

That would be scary. I encounter enough guitar players who don't know enough about their own instrument to know that there is a battery in there! I can't imagine how many guitar electronics would get damaged from lack of information.

And if it is that way for Colorado guitarists - just imagine the difficulty for bass players!

(ahhh yeah... never gets old...)

[Dave Labrecque]

That would be scary. I encounter enough guitar players who don't know enough about their own instrument to know that there is a battery in there! I can't imagine how many guitar electronics would get damaged from lack of information.

As someone who has fried a Beyer ribbon (as well as possessing qualifications as a dim-witted guitar player), I feel your pain, Angie.

[John Ludlow]

I wanted to provide an update to the rechargeable lithium ion 9 volt battery in a musical instrument question. As you will recall in our last episode, we left it that I would actually buy one of these beasts and actually try it out. Then, unbeknownst to everyone else, there was a long delay, as I dropped the proverbial ball and delayed ordering. At least part of the reason for that is that I discovered that a Sire bass, despite devoting a toggle switch to the choice of active vs. passive electronics, and having no document describing its function, apparently uses battery charge whenever it is plugged in - even when the toggle is set to passive electronics. So, I have been able to cause my batteries to last longer than a few days simply by not leaving it plugged in.

But, I have finally gotten back to it. My idea was that I needed two at a time for my bass. So, when they were exhausted, I would swap them out for two that were already pre-charged. So, I bought four of these:

https://www.amazon.com/EBL-USB-Rechargeable-Lithium-Batteries/dp/B086GTFGPP/ref=sr_1_9?crid=4JHLXMOI18GK&keywords=9+volt+recha rgeable+battery+ebl&qid=1641770493&sprefix=9+volt+ rechareable+b%2Caps%2C127&sr=8-9

Recall, that these are only 9v batteries in name. In reality, due to the vagueries of lithium ion chemistry, and bolstered by the fine print, they are actually only 8.4 volts. And there is a question as to whether 8.4 volts will sound the same as 9 volts does - with the details of the preamp circuit itself determining this. That was something only actually trying them out could verify.

This four-battery set comes with a USB-powered charging cable. On one side is the USB connector, on the other are 4 battery plug-ins suitable to connect to the EBL batteries themselves. Amazon provides a picture, if that isn't clear.

I have a couple of old wall-plug-to-USB phone chargers. I connected the charging cable, on one side, to the four batteries, and to the USB connection on the charging plug-in on the other - and plugged it in. In short order, the little viewing hole on the batteries began to emit a red light - signaling that charging had commenced. Later, I checked, and the little viewing hole on all four batteries had changed to blue - signaling that charging had completed.

Terrific. Charging accomplished.

Then, I removed the batteries from the charging cable and checked the voltage output of one of them using my ancient analog volt-ohm meter. 7.5 volts. Huh? Wait, am I reading the correct scale? Yes I was. The 9 volt battery, which was actually only an 8.4 volt battery, had finished charging and was putting out 7.5 volts. That can't be right, can it? Maybe my ancient VOM is out of adjustment? I got out a brand new 9v Duracell and tested it. It read just a shade over 9 volts. So - it's not the VOM.

Well... now what? Maybe they would charge better if I didn't charge all four at once? Seemed unlikely, but worth a try. So, I plugged two batteries back into the charging cable and again plugged it back into the wall. Again, they flashed the red charging light. A little later I checked and they were glowing blue again. Again - tested the result with my VOM. Again - 7.5 volts. Just to thwart Murphy, I reduced the charging batteries to one and tried it again. Still 7.5 volts on the other side.

As a result, I'm not very impressed with these batteries, y'all. I'm going to try two more tests, just to be sure. The first will be one in which I use a different wall-plug to USB connector. Presuming that gives the same result, I'll try running the charge in two of them down and then re-charging them again. There is some vague verbiage in the included battery 'instruction sheet' that indicates that the charge might last longer after a few cycles. Maybe, at that point, the batteries will actually make it to 8.4 volts.

Or... maybe not. I'll let you know.

[jmh]

That voltage (while disappointingly out of spec) may work ok. With conventional batteries, the voltage will droop on a curve according to load and duration of the load, so it is possible that in service, the lithium may be able to deliver continuous voltage that might give steady performance equal to so many minutes into conventional battery usage at a given load - and that may compare to relatively fresh batteries.

How do they sound? My concern would be that the regulation circuit may impose audible artifacts on the circuit or pickups.