LilyPad Coin Cell Battery Holder - Switched - 20mm

Sure, your flashing, chip-tune playing t-shirt is really cool at the party... but at some point you need to turn it off. And yes, you could just pull the battery, or maybe you've even sewn a LilyPad slide switch in-line. Wouldn't it be nice if there was just a switch *on *the battery? Well look no further.

This LilyPad Coin Cell Battery Holder has a small slide switch installed on the board, in-line with the power so you can shut off your project and save batteries. This slide switch is the same as is found on the LilyPad slide switch board, so it's not easy to accidentally turn off or on.

Just like the original Coin Cell Battery Holder, this simple board holds a 20mm coin cell battery (such as a CR2032) and gives you 4 connection points (two positive and two negative) for sewing into your project.

Note: A portion of this sale is given back to Dr. Leah Buechley for continued development and education of e-textiles.


LilyPad Coin Cell Battery Holder - Switched - 20mm Product Help and Resources

Core Skill: DIY

Whether it's for assembling a kit, hacking an enclosure, or creating your own parts; the DIY skill is all about knowing how to use tools and the techniques associated with them.


Skill Level: Noob - Basic assembly is required. You may need to provide your own basic tools like a screwdriver, hammer or scissors. Power tools or custom parts are not required. Instructions will be included and easy to follow. Sewing may be required, but only with included patterns.
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Core Skill: Electrical Prototyping

If it requires power, you need to know how much, what all the pins do, and how to hook it up. You may need to reference datasheets, schematics, and know the ins and outs of electronics.

1 Electrical Prototyping

Skill Level: Noob - You don't need to reference a datasheet, but you will need to know basic power requirements.
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Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • Member #457354 / about 11 years ago / 3

    How many LED's can you connect to this?

    • red913 / about 10 years ago / 1

      The more LED's the less voltage to each and the dimmer they get. I think I read somewhere 3 or 4 works.

      • BigHomie / about 10 years ago / 1

        That's only if they're in series. If the LEDs are wired in parallel, like Christmas lights, then they share voltage, and the current is divided amonst them. Then, how long the battery lasts depends on how many LEDs are wired in parallel, so if you have 100 LEDs in parallel that draw 5mA each connected to a 1000mAH coin cell, you can run all the LEDs for 1000mAH/(5mA*100LEDs) = 2 hours, or mix and match.

  • Member #512684 / about 9 years ago / 1

    There 2 outputs on this board. Are they both connected to the switch? When it is turned off, do both connections go dead? Just wondering.

  • red913 / about 10 years ago / 1

    So when using this with something like a white LED, the battery goes below the Vf of the LED very quickly. Is there a boost converter or something that will allow me to keep the voltage high enough to fully use the battery on LED's like that?

    Perhaps we need a boost converter Lilly pad?

  • Member #495315 / about 10 years ago / 1

    How good does this hold up during washes? We are looking to use this in a scarf that will be washed.

  • Member #529497 / about 10 years ago / 1

    Can this power an Adafruit Flora or Gemma?

    • Member #512684 / about 9 years ago / 1

      No. Flora and Gemma need closer to 5 volts for that. They can run on a coin cell, but it won't be very stable and the capacity of the battery is so low that you might get an hour or so out of the battery before it goes dead.

  • ari6126 / about 11 years ago / 1

    On mine the switch popped right off. Maybe some glue under the two plastic pins that go through the board would help.

  • Member #412831 / about 11 years ago / 1

    Hi, I was wondering when this product might be back in stock please?

  • Roger7 / about 12 years ago / 1

    The combination of the battery holder and the switch was so practical, I had to get some right away. However, the solder joints that attach the battery holder were incredibly weak. Installing a battery caused the metal frame to pop off. Both of the boards that I bought had this problem. Re-soldering secures it nicely, but it's a little awkward soldering on the shirt I had already sewn it into. I suggest reinforcing the solder joints that hold the battery frame before use. Oh, and don't hold the frame with your finger while you are soldering it. :-)

    • Same thing happened to me. The casing just popped off and the joints don't take rosen core solder very well, at least when I tried it.

      • Josh Desu / about 10 years ago / 1

        Yep, I just designed a board that used that exact coin holder and we had the same problem of the holders popping off frequently. Learning from that, as we were hand soldering them, we just made sure that the solder mounded over coin cell holder tabs, and then we were good to go. It doesn't look like (from the picture) that they've changed the manufacturing process to do that, so maybe you'll want to go and throw more solder on there before sewing into the project. It's not as pretty of a solder joint but hey... better than the holder popping off.

Customer Reviews

4.3 out of 5

Based on 19 ratings:

Currently viewing all customer reviews.

1 of 1 found this helpful:

Does the job, weak battery holder

This does the job of adding a battery to the project fine. The on off switch is nice. I got two of these this month (march 2015) and one had the battery holder pop off on first use. Had to put on my reflow skillet and add more solder. Holding fine so far.

Way to fix the board! Nice work. So sorry that it popped off in the first place. If you ever have troubles, please feel free to contact our Support staff and we'll do our best to help resolve the issue. Cheers

Sewable Circuits at Middle School Makerspace

I recently used 2 LilyPad Coin Cell Battery Holders at our school Makerspace and they worked beautifully. It was easy to sew with them using conductive thread and therefore easy to make a complete circuit to light up a sewable LED. There is a small on/off switch so the battery isn’t drained. Great product!

Great incentive for grade 6,7, & 8 Sewing Class!

I designed a felt wristband with a circuit on it it that lights up if properly sewn. Boys and girls both strongly invest in the project. No kid can tell me they are satisfied with their project if it won't light so we explore until we find the problem. It is always a short they don't see. They have to develop some patience to find the problem. Great learning tool!

Best thing ever!

Such a shame that there aren't many of these out on the market, this little bugger made my DIY modding project a lot cleaner looking and more compact with me not needing a coin cell battery holder AND a small toggle switch. Great product!

battery holder popped off on 3/15 that I ordered

The solder weld on the tabs is really weak...please fix this problem: when working with teenagers it can be a deal breaker to have their project fail after weeks of sewing.

So sorry to hear about that issue. These are generally pretty solid. If you have ones that fall apart, please contact our Technical Support team. They will be more than happy to help you.

Great switch but weak battery holder

The switch is perfect. The board and solder points are great. The battery holder attachment to the board is a little weak and some of them had to be fiddled with and pressed together to have proper contact.

Perfect for project

This is my first experience with LilyPad. Used to power 2 yellow LED owl eyes for Halloween costume I created. Holder's small size allowed me to easily hide it under a felt feather in back of hood, which can be lifted to turn on and off. Will definitely be using for future projects.

Pretty neat!

Stitched in well, the soldering is solid, and the convenience of a switched battery is great. I did get some weird behavior when I first got it in a circuit where shaking it while in the off position seemed to have some intermittent power to the LEDs. Not sure if the switch was not fully off, or if the switch has some vibrational sensitivity. But all seems fine recently.

Easily Broken

The casing for the battery WILL come off easily. There are many others comments stretching a quite a while back. I had to resort to reattaching it back on my own. Will not be likely to purchase another :(

If you ever have troubles, please feel free to contact our Support staff and we’ll do our best to help resolve the issue. Cheers


In my last order there was on battery holder that the solder did not work, but all was fine with this one. Will continue to purchase Lily Pad product!!

Broke during first use

Well, I took it out of the package, put the battery in, and one side of the surface mount solder joints popped off immediately. So as of right now it is unusable.

Great for small projects!

Love that this combines the battery holder and switch together. Works great for small projects where space is at a premium!

Very nice for coin cell battery, but...!

This is just what I ordered for a small 3 volt LED lighting circuit, but it is really on a 30-32mm CB Pad. I'd like to see a double sided LilyPad Button Cell Holder for 2 LR44 batteries (1 each side - 3 volts total) with switch that would fit on your 20mm CB Pad. This smaller size would lend itself to many more uses, including small model lighting. Hope to see this product soon. Good luck.

Good development on sewable battery holders and switches

This is a great battery holder and small switch for sewable applications. Inexpensive and less cumbersome than a separate switch and battery holder.

Very helpful for teachers and students creating e-textiles

I teach an introductory course in robotics, covering mechanical, electrical/electronic and programming to K-12 teachers. Therefore it's important that the projects are engaging and substantive without being overwhelming. The Lilypad battery holder is very helpful in creating etextiles using conductive thread. Because this power source via the coin cell battery is easy to place and sew, one can focus on sewing the lines of circuits connected to it and led lights (also Lilypad) on fabric. We use the switched version as it provides a finished and cool feature to their projects. It costs $1.00 more than the unswitched version, which I have used in the past to save money, but it's worth it - especially with the educator's discount. Take the battery out and you can wash the textile project. Great for kids!

Good for my wearable electronic bracelet

I was able to sew the holder right into a bracelet using steel thread, as it is lightweight and provides four holes for connecting. The connections worked well. The on/off switch should make it versatile for a number of applications. It fits a CR2025 coin cell battery.