We are facing a problem of how to make 2 or more flat-end battery series. Because of the flat poles of a battery, when we need a battery series, we can make a 2 batter series of 18650/26650 into a double Li-Ion battery series!
In long time, we use a little magnet to adhere on one end of a battery to resolve this problem. like this:
While there will be new problem: the magnets are not central most time;or some battery has not a magnetic cap so you cant adhere magnets to it…… Even,because the little magnets are easy to make a short-circut, And even we dont warry about the safe problem, the magnets are not good conductors for their materials.
Now,we designed a connector to resolve this problem,it will be good conductor and centralize very well : the gold-plating connector with 2 little gold-plating springs:
Now, the 2 batteris can be well conducted each ohter.
It is a small part, it can do a well thing too.
Not categorical.
This solution can be compressed down do the PCB-thickness.
A piece of copper can’t do that - and in worst case this means, that your tailcap doesn’t make contact because the batteries are too long.
What a simple but ingenious solution-just ordered a few of each kind.
I too would prefer a Paypal option on your site- I think that this option is available
from other Aliexpress sellers.