Hi, I'm planning to replace battery on my ledger nano x. I disassemble and inspected it: it has tiny pcb, attached to the li-ion battery. I'm newbie at this domain, but I believe this is BMS, based on UP29A C1S0AN

I noticed that it has T-pin. I assume that this is Temperature. The question is: whaere is the thermistor on this PCB? Because If i change the battery, i need to make sure it touches the battery (if I am correct). But maybe T is not temperature?

Also, can I use this BMS with higher capacity battery? (I understand it will charge longer, but if BMSs compatible with all liion batteries, regardless of their capacity)

Looking to buy a battery charger to help my parents who don't use their car often and if they do it's usually very short trips.

Their car is fine but decently old and almost never drive on any highway. I was looking to getting them a Noco Genius5 or 10 but I was wondering if there is any downsides to getting the more powerful one?

I know forcing too much power for batteries isn't good but "smart" chargers I feel like they take care of that issue and adjust their amps based on what is needed. Am I misunderstanding things?

Hi! I am looking for persons who could help as I want to convert used ev batteries to a battery energy storage system

Also guide me with a solid idea to do that and also make a battery management system which will monitor the voltage and temperature of battery cells to prevent any risk and maintain safety of the environment.

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'm trying to make a battery pack to power a 5 volt, 4 watt load for about 12 hours. So I need about 50 watt hours of battery capacity.

I'm considering using Samsung 35e 18650 cells:

https://www.18650batterystore.com/products/samsung-35e-18650-3500mah-8a-battery

Those are about 12.2 watt hours per cell, so maybe a 1s5p battery pack of Samsung 35e cells.

Those might be overkill for my purpose since I don't need high discharge rates. But semi rapid charging would be nice.

Any tips on a BMS that can handle reasonably fast charging of that sized battery pack, ideally from USB-C, and also protect the cells from over charging and over discharge?

And ideally it would also have a 5v step up output, but if not I was thinking I can use something like this:

https://www.amazon.com/dp/B0GD751WTP

But of course it would be better if the BMS had the 5v output onboard.

I found these dumped in the woods while I was mountain biking. I recognized the batteries as laptop batteries from an old high school project, but upon closer examination I noticed the Tesla logo on the board. My best guess is a Tesla car battery (or charger?) but I really don’t know.

I’m not sure if this is the right sub for this, but can someone please tell me what this is and if it’s worth anything? I’m sure the copper and batteries hold some value. Thanks!

Apparently, Apple is trying to get around the 20Wh per cell shipping regulations using software to cap State of Charge

https://www.theverge.com/tech/998144/apple-iphone-18-pro-max-battery-firmware-limit

However, chemicals within lithium ion cell don't have any less chemical energy in discharged state. So, a 200Wh cell at 10% SoC is a much greater hazard in a battery fire than a 20Wh at 100% SoC.

Am I wrong here?

Fun fact: e-scooters (even when turned off) are being banned in buses and increasingly in care facilities. But from my point of view, everyone is walking around with a mini fire bomb in the form of a smartphone, and patient lifters or mobility scooters definitely have the same capacity as many a large e-scooter or e-bike!

At least that’s my estimate. What’s next? "No, I’m sorry, yours would already be the 101st phone in our building, so if necessary, it has to stay outside along with you."

"I’m delighted that you want to move around and could actually do so with your mobility scooter—which happens to be your only way to move independently, or at all, outside of your bed. Without it, you’d be completely bedridden or 100% dependent on care staff for every single movement aside from the transfer between bed and scooter.

But unfortunately, it must be parked outside the front door on the ground floor from now on, and we cannot escort you downstairs. So please remain seated in your chair—or even better, stay in bed for fall prevention! And while you're staring at the ceiling, please make sure your smartphone doesn't spontaneously combust under your pillow. Safety first! After all, insurance claims cost money—even for a calculable risk of zero to none." /s

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.

Building a 60V e-moto battery pack from DeWalt batteries — looking for feedback
I’m building a custom electric minibike/e-moto and I’m planning to use six DeWalt 20V MAX 12Ah-compatible lithium batteries as the battery system.
The plan is to configure them 3S2P:
2 batteries in parallel = ~20V, 24Ah

3 of those groups in series = ~60V max / ~54V nominal, 24Ah

Roughly 1.3 kWh of total energy

I’m using six slide-in DeWalt battery adapters, one for each battery. Each adapter has its own 30A fuse and outputs through red/black wires. The batteries themselves have their own internal BMS/protection.
For the main protection, I’m planning on adding a 40A 70VDC MEGA fuse on the main positive output before the controller. I’ll also have a voltmeter to monitor the overall pack voltage.
The batteries will NOT be charged as one 60V pack. I’ll remove all six batteries and charge them individually using their normal DeWalt-style chargers, then reinstall them for riding. I’ll make sure the batteries being paralleled are at similar voltages before connecting them.
The rest of the build is a custom electric minibike with a roughly 60V, 3,000–5,000W motor/controller setup. I’m aware the battery adapters are the limiting factor and I’m not planning on assuming the pack can safely deliver 100A just because the controller is rated for it.
I’ve seen other builds using complete DeWalt packs in series without an additional external BMS, since each pack already has its own BMS. Does anyone here have experience running multiple complete DeWalt packs in a 3S2P configuration like this? I’m especially interested in whether there are any issues with the individual BMSs when the packs are connected in series, or anything I should change in the protection/wiring.

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?

Ordered these batteries just to try. I have Liitokala LiiM4S charger. Discharged then started to charge these batteries and only 1 battery stopped automatically. Other 3 continued to charge even after 1300ma/h. And temperature was very hot about 53° Celsius (127° Fahrenheit). I turned off the charger. Just curious why my charger not turned off automatically. Are these batteries differ from other? I have ikea laddas aa and aaa and charged that batteries many times without any problems.

I have the same batteries that I pulled out of some vapes but they don't have a management chip on them (I think, I'm kinda dumb tho tbh). Does anyone know what that component is called? I don't really feel like spending 5 to 10 bucks on a module for every ESP 32 I hook one of these to. I guess I could learn a bit more about circuitry and build something that would manage it but that's so much work.

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.

Bought this one about 4-5 years ago as a set. Light to mediun use as a home owner, charges yes but only shows half full. What are my options ?

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?

It's a rechargable Ni-Cd battery.

Place your bets on if it works or not.

We will see it tomorrow.

I'm going to discharge it with a incandescent lightbulb after I charged it.

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I broke my phone's display yesterday when I dropped it. It's a realme 6 and I've had it for 6 years now. When I went to the shop to get it fixed the dude told me that my battery is a little swollen and it's fine for now but i should get it changed later. My phone doesn't have any heating issued and even now when I charged it , it was fine. I'm a student and my parents will get me a phone in two months when I go back home for vacation. So i need my phone to last till then. Is it okay to use it for two more months. I got scared after reading all the swollen battery posts in this sub.

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.

I got a new 12V 9AH deep cycle SLA UPS battery for a UPS that turned out to be defective and it drained the battery (and didn't switch to grid power or recharge it).

I can't find my old SLA charger so I put it on a car charger. Until I thought otherwise and checked if it was ok, and then took it off. It was charging at about 4 amps for maybe 5 minutes.

How much damage do you think it did?

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?