Blackmagic 6k g2 OEM battery

I just purchased a 6k g2 and I have a question about the internal battery. I have 3 np-f570 batteries. The one I got with it (used G2) and one that I purchased used from BH both have generic branding compared to the battery I purchased new from BH. The used battery was sold as a “Blackmagic Design “ battery from BH. However, on their site the OEM BM battery pictures show the non-branded battery. Are the non-Blackmagic branded batteries lower powered generics? The reason I ask is there’s a significant bump in run time/price between the two. Thanks