OM SystemOLYMPUS BLH-1 Rechargeable Battery, black

I conducted two tests with the Olympus BLH-1 and the Wasabi and Power2000 fully decoded clones. The first test was a controlled-lighting tripod-mount time lapse on an E-M1.2 at 1 minute intervals with the screen active. The second test was a constant current discharge to 7.2V at a rate which resulted in discharge time roughly matching the number of pictures taken in the first test. The 7.2V cut-off point was chosen as that appears to be when the E-M1.2 powers off - batteries consistently measured around 7.4V after shut-off, which at a 500mA current drops to around 7.2V.As is to be expected, the Olympus BLH-1 matched the best of the two clones that I tested in terms of capacity at around 1500mAh. The Wasabi 2 pack had one battery also measure around 1500mAh while the other was only around 1200mAh. Meanwhile both Power2000 batteries only measured around 800mAh.So why would I recommend the Olympus BLH-1 for most when the Wasabi 2 pack costs the same and provides anywhere from 80% to 100% the capacity? Well, the variability is one mark against the Wasabi - it's clear they're not using a single supplier/specification for their 18500 cells given the variance I observed. Second is that the circuitry within the battery isn't quite on par with the Olympus as there's no mechanism for charge-balancing between the two cells. Charge-balancing circuitry ensures that both cells are always fully charged by effectively charging each cell individually. The BLH-1 clones lack this circuitry and instead charge the two cells serially, which over many charge-discharge cycles invariably results in one cell having a higher state of charge than the other due to minute differences in charge rate between them. This results in a much faster reduction in usable battery capacity as the battery will stop charging soon as one cell is fully charged even if the other is only half charged, while on the discharge side the camera will turn off soon after one cell is mostly 'discharged'.

Over the years I have cheaped out from time to time, and it's usually not worth it. My off-brand batteries (though, presumably from an OK supplier) have all expanded and won't fit any longer. Now that my batteries can be charged with USB-C in-camera I would not trust third party batteries any longer.OEM batteries cost an arm and a leg, but for longer trips I now take two/three OEM bateres and a big USB-C power bank, and recharge in the field.

My previous Olympus cameras used BLN-1 batteries, and third-party options had always worked almost as good as the Olympus batteries, and getting two replacement batteries for less than half the price of one original is a bargain that was hard to pass up.But finding good BLH-1 batteries for my EM1-II has proven to be a challenge. I tried several different third party brands and none of them last even half as long as the originals, and one swelled up so badly that it could no longer fit in the camera. Not sure why that's the case with the BLH-1 clones, but after my third set of crappy replacements, I finally gave in an bought the Olympus brand.The good thing I can say about this battery is that it will give you the longest lasting and most stable performance for your EM1-II. The downside is the price and the charger that comes with it. Third-party chargers are way better since they offer options like multiple battery charging and/or the ability to be plugged directly into a socket instead of dealing with wires.

I have usually purchased third party batteries for the many cameras I've used over the years and never had a problem with them. Certainly they have never lasted as long as the OEM battery, but the cost difference made them the better value. In this case, with the BLH-1 Olympus battery, that did not hold true as the believable fully decoded third party batteries were surprisingly high priced. Less than the Olympus for sure, but too close in price for my taste.The next concern was would I get a real OEM battery as one always sees claims of counterfeits. I made certain to order from Amazon as the seller and received a sealed Olympus box with a pristine battery and case. It is perfect and it's performance clearly matches the original battery. I'm happy with my choice to get this battery and thought it might help some to share that.

Ask anyone who takes a lot of pictures.... goes out and blasts of a couple hundred pics a day or more. It SUCKS when your battery dies. Like so many items from China, battery values are so overblown I will NEVER EVER EVER buy a third party battery from China again... the ONLY 3rd party battery I might go with if I can't get an Olympus original is a Watson battery.... they seem about as close as you'll get to the real deal. These may cost more money, but they will pay you back with as long a life as you will find in a battery for your camera.

its a battery that works according to specs -the visual of an off brand battery melting in my M1 mark iii gave me no choice but to go with the home team -you have olympus qaulity for olympus quality cameras - fit - finish - performance-

I have had these batteries for six months and they are great. They charge very fast and keep the charge.

Having learned the hard way about 3rd party battery 'replacements', I didnt even bother with my new Olympus EM1 MkIII, went straight to the vendor.It fits perfectly in the camera, slides in and out easily. 3rd party batteries frequently dont fit 'quite' right - i've had more than one get stuck in the camera requiring some tool work to remove.Holds a charge well. Lasts long. (these are other faults of 3rd party batteries, not holding a charge, or having a sudden drop off in charge - i.e., one moment the battery shows full, the next youre getting battery empty notice)So, for professional phtographers, I always recommend spending more and going with the OEM battery.