USB D Lithium ion Rechargeable Battery, High Capacity 1.5V 12000mWh Rechargeable D Battery, 4 H Fast Charge, 1200 Cycle with Type C Port Cable, Constant Output,2-Pack

I have been looking for a suitable replacement for the D Cell batteries that my equipment needs. I've tried various brands of the large capacity NiMh batteries and none worked properly. Immediately upon installing freshly charged NiMh batteries, my device would show the batteries where at half capacity (as detected by the equipment). After 45 minutes to an hour it would start to tell me it was time to turn off due to battery depletion. So I decided to give the 1.5 Volt D Cell Lithium rechargeables a try. I was a bit dubious but what the heck. I ordered 2 sets of the D1 batteries (a total of 4 batteries, my device requires 3). I gave them an initial charge and plopped them in. Well, much to my surprise, after 5 hours the device was still showing a full charge. I had never gotten this even with brand new high quality Alkalines. I turned off the equipment and waited a couple of minutes to see if the device would go through a cold start because it draws a bit more current from a turned off condition. No problem, it started right up showing a full charge. At this point I ordered a couple more sets so I would have a back up. The only thing left to see is how fast these will self discharge. Since the battery is always in an active state it has to draw at least a small amount of current, so I don't expect them to have the same shelf life of a regular style battery. Anyway, I just wanted to say that I am very happy with these batteries. Hopefully I with get many cycles out of them.

I can’t believe I’ve been using my batteries for over 4 years on a regular basis in a fan. They take a little longer to charge now. These would probably be equivalent to an EV with 200,000 miles on it.

Too soon to rate durability. Charging circuitry with indicator light is built into the battery. Batteries were charged when received, which is a plus. Packaging should include some kind of charging instructions. The first time I plugged in the charging cable, I didn't notice the indicator lights and thus had no idea how long to charge. The second time, the indicator lights flashed red, and I had no idea what that meant. I assumed it meant that the batteries were charging, which turned out to be correct, and let them charge; eventually, the the light was a constant red, which apparently means the charging is complete. Can you then leave the batteries to trickle charge, or do you have to remove them before you damage them? Who knows? I'm removing them to be on the safe side. No information on warranty. There is an email address for questions, with a top level domain of cc, which means the Australian Cocos Islands. Good luck visiting their headquarters. The product specs out well, the price seems good for what you get. User and warranty information is lacking, and manufacturer has little or no U.S. presence. I'm tentatively rating this 4/5 for the design, but questions abound; so caveat emptor.

I got these as they were comparable in price to non-rechargeable batteries. They charge quickly, have a quality look and feel, and come with the charger. I have a wall clock that uses a lot of juice as it has mechanical decorative gears. It will eat through batteries in a month when the moving parts are turned on- we have had the gears on along with the clock for about 2 months and it is still going strong! It’s nice to know I can pop them out for about an hour to charge- takes less time than a trip to the store or ordering more. I will be buying these in the future in more sizes as my battery collection runs out. I feel like these will last for decades of recharging!

The USB C connector is poorly stabilized internally so the connector cannot make a solid electrical connection. Therefore the battery does not even take a charge. this further causes the the Positive pin on the top to be dislocated or depressed, again because the internal charging module in the case is not stable and floating, instead of anchored as it should be. Therefore the led does not light. Sadly, I only used/or recharged this battery three times. It worked great for the three recharges. This was part of a flashlight for power outages. It failed when we needed it the most. There is no number or address to contact the manufacturer or seller directly.. I am an electrical engineer and the concept is great but the product quality and replacement support is not findable further wasting my time. If you are the manufacturer reading this, post your contact information or number so we can resolve this manufacturing defect.

Work great. Easy to charge

Can only feedback on the 2 batteries in the one pack I purchased but compared to other USB rechargeable batteries I've used these did not hold a charge for long and one almost immediately stopped holding a charge altogether - it appears to be indefinitely ^attempting^ to charge but the red LED only blinks and never goes solid (and demonstrably has no stored power). I would have gotten more utility and value out of a 2-pack of alkaline batteries though I hate the wastefulness of "disposable" batteries. Disappointed.

I recently got a new lightweight pump, and I was a bit shocked to find that it required d cell batteries. D cells are increasingly hard to source, and they are becoming a bit expensive. So I was pretty stoked to find these USB rechargeable d cell batteries, and at what I would consider a very reasonable price... about twice the price of a single set of alkaline details. These batteries have a tad more voltage at full charge then a fresh set of d cells, and when they run out they take about 40 minutes to charge. Already, in just a few weeks, I have recharged them about four times and that has saved me quite a lot of money.

One of the two batteries i. The pack was not able to charge as charger did not fit.

The batteries are very pricey. I replaced some Duracell batteries with them. Where the former lasted 3 months, these lasted 3 weeks before having to recharge, which is not great.