Project Farm on the Tubez did a GREAT video testing heaps of knockoff batteries and counterfeits versus the official batteries! Unbranded knockoffs were significantly better than branded fakes. I have an unbranded knockoff battery for a vacuum and it ROCKS.

I've bought a few off brand tools, but never the batteries. Interested to see how they'll hold up.

I've been using unbranded batteries for Ryobi for years. They have a LED gauge and they outlast the OEM batteries. I did a major construction job this spring summer and only the OEM batteries failed.

YouTube in invested is selling you OEM batteries but seriously, they are made in the same factory as the unbranded ones.

In Canada, a Ryobi battery @4Ah is $158 each. Generic 2 pack of 8Ah are $56. How can there be a 680% difference?

I have a bank of a dozen batteries and have never had an issue.

I bought a pair of 6 ah off brand makita batteries about a year ago, mostly to use in the kids power wheels instead of my good ones. They're still kicking I'm pretty impressed. I might have gotten lucky though, part of the lower cost is less quality assurance I imagine, so more of a dice roll to get decent ones.

A friend has his own electrical business, he buys unbranded batteries for all his DeWalt kit and claims never having an issue. He also says the higher capacity ones are really good.

That said there are dodgy ones out there. Buy from a reputable seller.

I've found off brand batteries to be hit or miss, but mostly hit. And for half the price I'll buy twice. After all, you can't tell what sort of 18650s they used.