I'm a Sony Alpha a6000 owner and am seriously considering this clever dual battery pack Prime Day Deal

llano 2-Pack NP-FW50 Batteries and Fast 18W Dual Charger — (Image credit: Future)

I'm constantly on the hunt for spare batteries for my Sony Alpha a6000 APS-C camera, and now I think I've found the perfect Amazon Prime Day deal on compatible batteries and chargers. The llano 2-Pack NP-FW50 Batteries and Fast 18W Dual Charger offers two batteries and a charging case is just $54.99 (was $69.99).

At 21% off, this sounds like a fantastic deal, but I also have a complicated history with my Sony cameras and the batteries I can use.

• Browse all early Prime Day deals at Amazon

It's been 16 years since I first started using a Sony Alpha. First, the NEX-5 (until the display died on the viewfinder-less body) and then the exquisite Sony Alpha a6000. Paired with my 200mm lens, they've been the perfect setup for my bird and astrophotography. But I've struggled with the batteries.

The Sony-brand Lithium-Ion rechargeable batteries that shipped with the NEX-5 worked with the a6000 I bought second-hand (new, the a6000 will run you almost $1,000), but eventually they stopped holding their charge, and I balked at the $70-per battery for the Sony-branded replacements. After all, I could easily find cheap knockoffs on Amazon (Prime Day or not) for as little as $26 for two (including a charge base!).

It's not unusual for me to wait until Amazon Prime Day to pick up a couple more replacements, and so that's how I stumbled on this llano deal. The two packs of batteries and a charging case that includes both a screen readout to tell you the charge level for each battery and a pair of SD card storage slots (not readers!) for just $54.99 is quite a deal.

Granted, the box offers no extra battery power, which means that if you want to charge the batteries, you do have to plug it in, but after that, you can just take the case with you. It's an efficient way to store and transport the batteries and to know at a glance, which one has enough charge for a day of use. The included batteries do, by the way, also support other compatible Sony cameras, including my old NEX-5, the NEX-7, A3000, A5000, A64000, along with other Sony camera models.

It's also worth noting that Ilano ships the same system in multiple versions for different batteries types, covering some of the best Canon, Fujifilm, Nikon and other Sony cameras (I've included shopping links to other Illano versions, further below).

The big caveat here is that these third party batteries are not usually as good or long-lasting as Sony originals. One thing to note is that while the llano batteries are listed as 9 volts, the Sony original is a 1,020mAh battery. In my experience with knock-off batteries that are often manufactured in China, they lose their ability to hold a full charge more quickly and dramatically than the Sony batteries.

Part of this has to do, I think, with the less sophisticated charging bases many of them ship with. In all fairness to llano, they usually don't look like this. They're not closable cases with LCD readouts, just one to three open bays where you drop in the batteries.

Ultimately, you will spend less and may have short-term relief for your Sony Alpha battery issues (nothing like having a pocket full of batteries on a long shoot), but you should not expect these batteries to perform long-term, like Sony originals, which, by the way, I have never seen included in Amazon Prime Day sales.