10Pcs Electric Car Bike Toy Battery 18650 Spacer Radiating Holder Bracket Black (WHL #22)
…and 10PC 18650 Battery 4×5 Cell Spacer Radiating Shell Plastic Holder Bracket KT0569 as well (yeah, the second one is misleading, I know).
Today, I have some mechanical parts in preparation for another project. These are stackable 18650 battery holders without electrical contacts. I have some more holders for pure storage and also single (non-stackable) battery holders with contacts, but these are something in between.
I actually ordered two variants of them, and as usual, a seller that has the one type doesn’t have the other in stock and vice versa – or they are super expensive. So I ended up buying from two separate shops at AliExpress. Meh.
The 2×1 type was 1.03€ for 10 pieces, while the 3×1 ones are 1.59€ per 10pcs, both including shipping. Note that you need two pieces per battery (one for each battery pole), so the ones I ordered are good to pack 10 and 15 cells respectively.
As you can see, they don’t differ much and they are stackable against each other. Basically, the 3×1 are just 50% longer to provide room for 50% more batteries…and they cost roughly 50% more. Perfect scaling – buy whatever you need, don’t get the 5×4 arrays and chop them down because you’re such a tight ass. 1×1 single cell holders are also available, but I don’t see the point in getting them. After all, these are just battery spacers to put several batteries close to each other. And as you can mix them (the array above stacks together just nicely), I cannot imagine the need for a single spacer for when you cannot combine the others in a meaningful way to make it work. If you have a single cell only…well, maybe strap it down the board with some zip ties
As I’m lazy, I didn’t bother to make the exact same pictures again for the 3×1 type. So here is the 2×1 spacer from all sides:
When stacking more complex figures, make sure to clip together rows first and then add block by block. Two sides are male and two are female, so they have a very firm grip once put together. I did an test array of 5×2 cells, and that’s already super stable without connecting the cells. I used 3×1 and 2×1 in series and put the inverse in the next row for maximum stability. The holder however does slip off unless you put one layer of Sellotape (Tesafilm) around a cell, as one of the red ones actually has.
If you want or need a tighter fit, you can do that to all cells. And yes, it is possible to use protected cells as well:
The black Enerpower cell in this example (not really worth the money in my opinion) has 18.6mm diameter on both ends and offers a snug fit in the holder. You can lift up the entire array, but it’s not worryingly tight (as to damage the PCB). The green Panasonic cell has standard 18.0mm at the (-) bottom and around 18.1mm at the (+) top. If you have a look at the full size image, you can see light shine through the left gap between holder and cell. So to me, the holders are perfect size – compatible with protected cells and custom protection sleeves, but not too large to make the cells wobble around.
Packing density is also good: The 5×2 array has outer dimensions of 102x42x61 mm³ including the ~2mm hooks on two sides (which can be removed if your battery assembly is complete). So there is almost no loss in z direction, which also needs some spacing for the terminals anyway. For x and y, that equals to 428 mm² per cell. The square footprint of a 18mm cell is 324mm², meaning 32% overhead of the array. For comparison: A storage box for two cells clocks in at 43x21x75 mm³, which is 451 mm² (+39%) per cell and also one entire centimeter extra in z. A box for four 18650 is 81x22x71 mm³ isn’t much better at 446 mm² (+38%) and a little less z overhead. For larger storage needs it might be even interesting to store the batteries in their future holders and skip the boxes entirely. After all, these are 40 to 60 cents per cell – one holder is not much more than 10 cents per cell. Yet the boxes are more convenient if you only need to grab a few cells instead of emptying your entire collection. Choose your poison.
Conclusion on this one: Cheap, sturdy, yet good molding quality for a reasonable fit. Actually, this cannot be made in the Wan Hung Lo factory as I cannot find a major point of criticism…