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Has anyone designed a charger that can charge the whole FR-4X battery pack?

joden

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Without needing to remove each battery?

IE: something with a similar 9 volt battery connector that can hook up to the (removed from accordion) battery pack?

I've got charger but it can only do 8 batteries at a time....be nice if I could hook up some sort of bridging cable to to the pack in toto
 
How long does it take you to swap individual batteries?

I have an old Ansmann charger that can handle up to 12 cells - similar to this one without the USB power ports.

I think it's better to charge the cells individually than to charge them as a pack.

Battery cells deteriorate at different rates. The problem with combining them in a pack is that if one cell goes bad, you don't know which one.
 
How long does it take you to swap individual batteries?

I have an old Ansmann charger that can handle up to 12 cells - similar to this one without the USB power ports.

I think it's better to charge the cells individually than to charge them as a pack.

Battery cells deteriorate at different rates. The problem with combining them in a pack is that if one cell goes bad, you don't know which one.

Yeah, true. I

It's not the swapping so much, as needing to run the charging cycle twice...each time taking about four hours, even though its the last two batteries
 
if you look at chargers for electric model airplanes, you will find what you need, and they are relatively inexpensive..
They can charge ni cads, nimh, lithium metal, and lithium polymer batteries. Generally they are rated for up to ten cell nimh for the cheaper ones, or 18 to 24 cells for the more expensive ones. I believe the Roland takes 10 ? Nimh. So you should be able to obtain a decent charger for about twenty dollars tops. I know this because I use several almost every day over the last twenty years or so. My chargers balance the pack, so the every cell is the same once it comes off the charge
 
thanks, I've got a 12 cell charger now, but what I was asking was if I could just plug in the entire battery holder using the 9volt batter connector
 
As long as your connector on the charger and on the pack match so that positive and negatives match….you can then just leave them in the holder and charge through the connector……they won’t be perfectly “balanced” but nor are they when you remove them from the charger you have. They may be the moment you remove them, but guaranteed in ten minutes sitting, they will no longer be. The difference in cells , as long as they are decent quality, won’t be noticeable.
I built a midi system for one of my accordions, and powered it with one 500 mah 9 volt cell through a voltage reducer. It powers my
Hohner musette lmmm accordion for as long as I can play…so far I have reached 4 hours, and still not discharged. No amp in the accordion though. I use battery power for the accordion, for the amp, and for my Ketron arranger. No cords at all… get to the job, plunk it down on the floor, turn it on and play. Never had a failure yet…I do though carry a spare battery pack just in case. If your charger is rated for up to 12 cells in series, you are good to go. ( 18 volts)
 
The batteries in the holder are connected in series. That won’t work by just connecting a charger with a 9-volt style connector. Anyway, what’s the big deal about taking the batteries out of the holder, putting them in a charger one-by-one and putting them back in the holder when they are charged?
 
The style of connector as long as it matches what is on the battery pack makes no difference what so ever…the charger sees how many cells it is charging, and uses the appropriate power. As long as the positive and negative terminals on the charger cable match those on the battery pack, you are good to go. Been charging batteries for twenty odd years in series, never had an issue. Once or twice a year, I check each cell for capacity. What I use batteries for in my other hobby is much more demanding than powering an accordion.
 
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so your charger has a voltmeter built in and logic to
analyze the result ?

i had only heard of simple threshold volt sensitivity built into chargers to
trip them from full rated amperage to trickle or maintainer amperage
which of course are also set for charging a pre-determined voltage
battery pack or wet cell

but a charger that can count the cells and set the charge current and voltage
accordiongly sounds pretty cool.. does that sophisticated circuitry add much to the cost ?

i guess a severely depleted pack or a dead cell could trick
such a charger to give an incorrect result as to the initial cell count

of course one doesn't need a very smart charger to fill a simple 12 volt pack
of tabbed AA cells shrink wrapped for convenience.. hundreds of such chargers
out there to choose from under 20 bucks that trickle around 300 milliamps
 
chargers that we use for Electric Model airplanes, have technology that we only dreamed about ten years ago. They sense Internal resistance of the cell, charge at full capacity until the cell gets to 90 percent, then drops the charge rate for the last few milliamps...as the top end is where the cells are damaged in a fast charge, but you can get 90 percent very quickly. some of the chargers are less money cost wise, than one set of batteries. i have three of the up to ten cell chargers that I purchased for less than a set of decent nimh batteries. At the moment I use Lithium ion batteries to power one of my midi accordions.....they give me roughly 10 hours play time...and the advantage is, if I charge them today, and don't use them for a month or two, they lose nothing in storage. I say roughly 10 hours, but I have not ever run them down to where they need a charge before I change them...I just put a fresh pack in every Gig. I have though played over ten hours on a charge and still register 60% on my battery checker.
being heavily into electric powered Rc airplane models BIG ones...I have become fairly up on batteries in the last 25 years.
todays chargers also sense battery temp. and if the temp goes high, they shut down automatically. When you hook up, the charger will tell you if you have a bad cell.
 
The style of connector as long as it matches what is on the battery pack makes no difference what so ever…the charger sees how many cells it is charging, and uses the appropriate power. As long as the positive and negative terminals on the charger cable match those on the battery pack, you are good to go. Been charging batteries for twenty odd years in series, never had an issue. Once or twice a year, I check each cell for capacity. What I use batteries for in my other hobby is much more demanding than powering an
chargers that we use for Electric Model airplanes, have technology that we only dreamed about ten years ago. They sense Internal resistance of the cell, charge at full capacity until the cell gets to 90 percent, then drops the charge rate for the last few milliamps...as the top end is where the cells are damaged in a fast charge, but you can get 90 percent very quickly. some of the chargers are less money cost wise, than one set of batteries. i have three of the up to ten cell chargers that I purchased for less than a set of decent nimh batteries. At the moment I use Lithium ion batteries to power one of my midi accordions.....they give me roughly 10 hours play time...and the advantage is, if I charge them today, and don't use them for a month or two, they lose nothing in storage. I say roughly 10 hours, but I have not ever run them down to where they need a charge before I change them...I just put a fresh pack in every Gig. I have though played over ten hours on a charge and still register 60% on my battery checker.
being heavily into electric powered Rc airplane models BIG ones...I have become fairly up on batteries in the last 25 years.
todays chargers also sense battery temp. and if the temp goes high, they shut down automatically. When you hook up, the charger will tell you if you have a bad cell.
So, are you using that kind of charger on the batteries in your FR-4x?
 
I knew I'd seen this before but could not find it until now...


There's one on Reverb.com for $166 plus an arm and a leg for shipping


I have no experience of it and to honest, it takes me two minutes to swap batteries. I keep three sets, one in the accordion, ate least one ready to go and the other on charge when it comes out of the accordion and then it's also ready to go.
 
Looks kind of hokey, and really over priced, that charger is likely worth about ten or fifteen dollars in the R.C. Hobby. The battery pack is about five or ten….add about fifty cents to solder a regulator, and you are up to a maximum of 20 to 25 and that’s Cdn funds….which is about thirty two cents U.S. :)
 
If you want to play while you are hooked to a cord, what would be the advantage,? just plug in your Roland power supply and play. This is just to avoid having to remove each cell from its holder and insert into a charger. It’s just a convenience thing. I have used a Roland, and didn’t much like it, and subsequently went to a different brand of accordion. Nothing to do with quality, or anything except personal preference. The midi accordion I went with has it’s own set of shall we say “issues” but the perfect midi accordion hasn’t been built yet. We poor working class types have budgetary restrictions, so we have to choose which dis advantages we wish to deal with. my dis advantage is having to always be hooked to a cord. But I prefer the sounds in my accordion to the Roland. AndjmI never have to worry about batteries.
 
Let us keep it simple…buy an extra battery holder and a couple cables. Even a spare battery cover. Purchase them directly from Roland is cost effective…
 
Without needing to remove each battery?

IE: something with a similar 9 volt battery connector that can hook up to the (removed from accordion) battery pack?

I've got charger but it can only do 8 batteries at a time....be nice if I could hook up some sort of bridging cable to to the pack in toto
I did. But:

- It’s for FR-1x, not FR-4x.
- There’s no need to remove the battery cells from the accordion to charge them.
- Frankly, I don’t use this new “feature” much. I’d rather charge & monitor each cell individually.

Read this thread.
 
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