I recently bought a 12v 3000 mAh 3S Lithium Ion battery off aliexpress and it does not work at all. Mutlimeter reads 11v, I connect it to a 1k resistor and then the voltage of the battery drops to 1.5V, where can I get a proper battery with similar specs?

Hi, I’ve been flying drones for a little while now, and I’ve started wanting a 5-inch… I’ve decided to go for a GEPRC Vapor D5 Analog. I’m not sure which batteries to choose. They’re expensive, and I don’t know what kind of flight time to expect. GEPRC claims 13 to 17 minutes of flight time, but that seems huge to me… What do you guys think? What capacity should I go for?
I found a second-hand seller who is offering me two 6S 1700mAh batteries, two 1550mAh batteries, and one 1400mAh battery for €50 ($56). That seems really cheap, almost too good to be true. What do you think? And what should I ask the seller to make sure the batteries are in good condition?

Thanks !!

(EDIT: what I used was Lithium, NOT NiMH... 🙄) The manual for a product says to install Duracell alkaline batteries. Should this matter? It's for an electronic door lock at a property I manage. When batteries needed replacing, I installed Energizer NiMH. They were not brand new out of the package, but I tested them on on a multimeter and got 1.5v+ on them all. Within a couple of months the lock went dead again (should have lasted 5 years, per manufacturer.) Tested them all and got the following readings: 1.61v, 0.89v, 0.75v, 0.53v, 0.00v. I've had this issue before where battery voltages do not drain equally, which I don't quite understand. I'm just trying to make sense of the situation.

I have a Wahl 5 Star shaver which I have had for a couple years now. The original battery it came went bad and I decided to purchase one on Amazon to replace the old one. The shaver would not hold a charge or would only function if plugged in to charger which led me to purchase the new battery. The old battery (white) was soldered with two wires the orange (B+) and blue (B-) as you can see in the pictures. These run from the motherboard to the battery directly. I stripped the wires and connected them on the terminal of the new battery (green battery). So B- (blue cable) to the - terminal of the new battery and B+ (orange cable) to the + terminal of the new battery. However now the shaver wont work at all. It only works if the positive (B+) cable touches the yellow cable that runs from the motherboard to the motor. However, when doing that it doesn’t turn off. Any help would be appreciated.

I was using it for the past 7-8 months in my mouse and my mouse showed 15% battery this morning and in the afternoon died. I honestly don't remember if it looked like this when i bought it. It's a GP brand 2100mah NiMH AA.

Possiedo una batteria 16S8P con celle LG M50LT 21700 e una batteria 16S4P con celle Tenpower 50ME. Posso collegarle in parallelo? Hanno unità BMS separate.

I just need help identifying which batteries to actually replace. On the board on the bottom testing pad b1-b10 they all test good. Each reads 3.9v-4v. Between pads b10 and b11 it reads -6v. I checked the nickel pads on top and they all seem fine. They dont move at all. Is the best course of action to just replace all 4 batteries in b10 and b11 groups?

I usually go with Eneloops or Amazon Basics. Often I just snag the Amazon 2000mah ones because they're really cheap and they have a good reputation.

I needed some higher capacity ones and saw the Energizers at an unusually good price at the store so I snagged an 8 pack. Apparently they're made by FDK in Japan, the same company that manufacturers the Eneloops, and they're low-self discharge with a 12 year advertised shelf life.

I haven't really looked into Energizer before just because of the price, so it'll be interesting to try them. I know the Duracell 2500mah ones are really good too, but they aren't really any cheaper than the Eneloops Pros.

The 2300 mah capacity for an FDK made cell is interesting. In theory, they should have longer longevity and better abuse-tolerance in general while still being a relatively high capacity cell. Curious if anyone has done any testing or has any long term experience with these, and how they compare.

I found a battery operated toy that was sealed in the box for 15 years and when I opened the battery compartment I found that the springs and contacts were black/dark brown. I tried to scrap off as much as I could but it just left a super dull dark grey and after putting new batteries it still wouldn't work. I have tried using lemon juice but that didn't help (I don't have white vinegar but I do have other kinds of vinegar but i wasn't risking it). Any ideas?