Frequently Asked Questions
Most of the questions we get asked are quite common and shared among many new users. Please check below to see if your question is already answered. If you don’t see your question, you can always heading over to the Forums for more support. We’re waiting over there to help you!
How easily do the caps snap together?
The caps slide together using a slick dovetail design that both aligns and locks the cells together. It takes a little bit more dexterity than children’s Lego bricks, but it’s pretty easy. See this article for more info on connecting the caps together.
How much current can the terminal caps support?
So far the caps have been tested and confirmed to withstand up to 3.5 A of current each. However, we are quite confident that they can carry higher levels of current and will testing this further soon!
Can cell level fuses be incorporated?
Can I use recycled/salvaged cells?
You can, though we always recommend that you use new cells for safety’s sake. It is impossible to know the quality of used or salvaged cells. But if you really want to, then of course you can use salvaged cells in VRUZEND battery building kits. You just might need to use a dremel or other tool to grind off the old spot welding bits on the terminals to ensure that the cell terminals are smooth and flat. That will give a better connection with the VRUZEND cap’s conductor.
What if I have to replace a cell in the future?
If you ever have to change a cell that goes bad, you can disassemble your VRUZEND battery pack the same way you built it, in reverse order. We recommend removing the bus bars on one side first so that the terminal caps can flex better. This will make the removal process easier. Start at one end and begin prying up the caps. You should be able to do it one column at a time. If you need to, you can use a piece of wood to help lever the caps up. Once the caps are removed from one side, you can take out the batteries and rearrange or replace them as you wish.
How do you charge the battery?
There are two ways to charge your battery built by a VRUZEND kit. 1) Use a BMS and a simple lithium battery charger, or 2) Use a balance charger.
If you use a BMS, you’ll wire it as shown in this article. Then you can just plug your charger into the charger port and you’ll be charging!
If you want to use a balance charger, you can wire a balance connector to your VRUZEND battery using the steps in this article.
Can you use any 18650 with the VRUZEND kit?
Pretty much, at least all the ones that we’ve tried so far. As long as the cells is made to the standard 18650 dimensions (approximately 18.5 mm in diameter) then it should fit. Some cells, especially recycled or repurposed cells, have wider heat shrink and you might just have to remove the heat shrink, or a portion of it at the ends of the cell, if you find those cells have an extra tight fit. That rarely occurs though, and pretty much every 18650 cell should be held in the cap just fine.
Will the nuts or terminal caps come loose from vibration?
The plastic material in the VRUZEND terminal caps actually helps prevent any vibration loosening of the nuts. The plastic compresses slightly when the nuts are tightened down, which creates some back pressure, preventing the nuts from loosening themselves. We’ve never seen nuts back off by themselves when properly tightened, but some people like to add a drop of hot glue to the nut as extra insurance, just in case. As for the cap itself, they fit very tightly to the cell and require a decent grip and muscle to remove. They aren’t going anywhere by accident…
What are the dimensions of the caps and of the cells with caps?
The caps are approximately 22 mm square. When added to an 18650 cell, the entire cell becomes approximately 93 mm long.
What is the weight of a pack/how much do the terminal caps weigh?
Each of the individual caps weighs approximately 4.6 grams, while a nut and bus bar combined weigh approximately 1.25 grams. An entire set of 100 caps, nuts and bus bars weighs approximately 650 grams (1.4 lbs), if you use all of them. The entire kit ends up adding around 1 to 1.5 lbs to a battery, depending on the size battery that you’re building.
Will the terminal caps melt?
Polypropylene (the plastic that the VRUZEND terminal caps are made out of) has a melting temperature of 266°F – 320°F (130°C to 160°C). Lithium batteries really shouldn’t be operated in conditions hotter than about 150°F (65°C). If your terminal caps melt, then you likely have bigger problems at the moment.
Can I build different shapes of battery packs with VRUZEND kits?
Absolutely! The VRUZEND terminal caps are literally building blocks that you can use to build many different sizes and shapes of custom batteries. The simplest and easiest shape is of course a square or rectangle, but you can be as creative as you want. Many electric bicycle batteries are triangles to fit into a bike frame, and a right triangle is easy to build with VRUZEND caps. Other shapes are easy too. As long as it fits a grid format, you can build pretty much anything shape.
What is the difference between the USA and international warehouses?
As you can imagine, the USA warehouse ships mostly to US and other North American addresses, while the international warehouse handles shipments to most of the rest of the world. Shipping in the US is much cheaper when the package starts in the US. That’s why we bulk ship inventory to the US, to reduce the shipping expense and time for US customers. What used to take at least 20 days from the international warehouse now takes 2-4 days in the US. The price in the US is slightly higher due to the import and freight charges, but the final price including US shipping is approximately the same or lower than the international shipping option (and arrives much quicker!). So whether you’re a US customer ordering from our Shop page or an international customer ordering from the international warehouse, you’ll be paying about the same low price either way!