Rechargeable D Cell Batteries 4 Pack, 1.5V 7500mwh Lithium LR20 Battery D Size with USB-C Charging Cable, for Flashlight, Toy, Radio

We bought these for a keyboard (piano). Theyre very lightweight but hold a charge for quite a long time. If you dont have a charger to fit these batteries, considering they're D's, they have a usb slot ( the small oval type ).

Good batteries

I was using a different brand that wasn't lasting long in my back motion light. I've been using alkaline batteries in that light for years, and they were lasting a long time. I use rechargeable lithium AA batteries in my security cameras, and they work great. Last pretty long. So, I started using rechargeable D batteries from the same company the AAs come from. The Ds were not working as advertised. So, VOLKATE was the next option up. First off - I do like the USB charging. WAY more convenient and quicker than my charger. Next - these do NOT last long in colder weather. The product says -4F - that is FALSE. These don't last more than a couple days out in <30F - and this is a motion light that doesn't go off unless there's movement. My dogs aren't out long in colder weather. They do their business then come back in. These lights go on when the dogs go out the door, but goes back off when the dogs are out toward the back of the fence doing their thing. Then back on again when they come inside. No other movement out there the rest of the night. I had to pull these out every couple of days to recharge. Warmer weather is here, so we'll see how it goes. So far, they've been in my light for several days and it's been 50F or above. So, that's better than it was this past winter. Hope they aren't a waste of my money

Light, easy to charge, long lasting

Got these to run RV refrigerator air circulation fan. They charged fast and lasted long. Will update in time if this changes but so far so good.

This is a review of the VOLKATE Lithium-ion Rechargeable D-Cell Batteries. The batteries are supplied as a pair with a special USB-C recharging cable which plugs into a USB-A power outlet and terminates in two (2) USB-C connectors. The batteries are designed with USB-C ports in the side of each battery for recharging the batteries. The batteries have the standard 1.5-volt output so there will be no problem with using them to replace standard alkaline-type D-Cell batteries. The specifications on these batteries are: 1.5 volts, 5000mAh, and 7500mWh. While these batteries have only about one-third of the capacity of most current alkaline chemistry D-cell batteries, the Amazon Seller says that they can be recharged up to 1000 times. Additionally, the lithium-ion battery’s chemistry allows them to output the specified voltage until they are almost completely exhausted. The design of the lithium-ion batteries also means that the batteries have minimal self-discharge so they do not simply die over time, even if they are not used. Lastly, these batteries are very light when compared with alkaline-type D-cell batteries currently on the market. When I received the batteries, I set them up to be recharged. They charged to full capacity very quickly. One took about thirty-five minutes while the second one took about forty-five minutes. I have no idea how close to being fully charged they were when they were received. I immediately noted that a red light shone from the top of the battery when they were being charged. Once they were fully charged, the red light changed to green indicating that they were fully charged and ready to be used. The batteries were noted to get slightly warmer than room temperature while they were charging. After they were fully charged, I placed these batteries into my D-Cell Maglite with an LED conversion unit. They worked just fine but I did note that my Maglite was significantly lighter with these batteries. I used my Maglite for about 20 minutes and there was no degradation of the light’s performance during this time. I then removed these new batteries and hooked them up to be recharged. That process took less than five minutes, so there was very little depletion of their charge during the test. I like these batteries for several key reasons. They are very light, they will retain their charge over time, the voltage output will not drop during use until the batteries are almost totally consumed, and finally, they can be recharged many, many times.

I really like these Lithium-Ion "D" formfactor batteries! My pair charges to 1.54v. I am using them in one of my two 2D-cell Maglite-style LED flashlights. I use the test flashlight twice a day, at least, for final & initial security walkabout, after dark & before first light, at home. It took awhile before my brain got the memo that LIGHT flashlight did not mean, "OOPS! No batteries!" For reference, @ 1.5v 7.5Wh = 5.0Ah (for such simple applications: Ah x V = Wh) Wikipedia reports that D-cell alkaline batteries sport capacities of 12-18AH so these Li-Ion batteries sport only 28%-42% of the a regular battery ... BUT ... most regular D-cell batteries cost $1 or more apiece while these Li-Ions can be recharged MANY times. From my point of view there are 2 downsides to this product; [1] I have a rather healthy stockpile of new D-cell alkalines on-hand <sigh> and [2] if I ever find that I have to use my flashlight to DONK some miscreant during "rounds" it will take extra effort because these new Li-Ions batteries make the flashlight so-o-o-o-o light. ;) I rate this product as a clear WINNER for the described and/or like purposes! AND they come with a sweet little C<-A 2-1 charging cable. ;)

Sorry to say not good . 2 out of the 4 I bought did not work. I wish I could return but can't. I all so bought AAA and the same thing 1 did not work and one stoped working. Do not buy.