You have replaced a battery with a rechargeable battery. You have thus solved all energy problems of humanity. I thank you on behalf of all future generations.
I went down this path a few years ago but about a year ago, I switched over to Lithium Iron AA cells, a better 1 for 2 swap out, voltage wise. As for flat top cells, I got some small rare earth magnets and they stick to the positive battery terminal - no spot welding required. You can also get button top Lithium 14500 cells. I also bought some AA cell 'blanks', I think they are hollow inside with an internal (+ to -) shorting wire, easier to use.
Another option is to use 14450 cells and a small buck regulator and then it's a 1 for 1 swap and you don't have any capacity loss, maybe even a little gain.
Note to anyone doing this. 1. Be VERY careful to get your voltage exactly right. 2. Soldering nickel strips to LIon batteries could cause a fire if you're not skilled. Also consider just buying AA & AAA NiMh batteries. They're the right voltage, last 10 yrs and only cost about $1- $3ea 👍
also label your device on the battery cover to indicate they are recheargable or put don't dispose recharge note on the unit....i had a friend who said his son and wife threw away all the expensive batteries he bought not knowing they are lithium/nimh ......ouch !!!!....i still grin and laugh when ever i remember the story !!
Yup overheating lithium batteries is bad. The best way to solder them if you don't have an impulse welder is to first clean the contact points with fine carbide sandpaper. Next apply a smear of plumbers tinning flux. Next tin with good quality leaded electronic solder, do this with a hot iron and quick. Next solder your wires or button tabs. I found the steel positive button from used up dollar tree AA or AAA cheap disposables works best.
I replaced ALL my AA & AAA alkaline batteries with NiMh batteries 25 yrs ago. I got most of them from old "dead" Nokia & Ericsson analog phone battery packs 😁 The screw idea is ok, but wooden dowel, 2 thumb tacks and a folded foil strip is cheaper.
Or you can just completely wrap the dowel (or an old, dead cell) with a layer of foil and either twist the ends or fold over and let the springs hold it.
Nice! At 12:15 I would migrate the spring down to the bottom so you don't have to modify your battery. With your nickel strips and welder it would be short work to cut and join and swap the middle terminals around. That way your batteries are all modded the same way.
What Ive been doing in my devices that take 2-3 AA batteries in series is I just replace them all with a single 18650 so I have the same or more amperage. If there is room for 3 single AA there is usually room for a single 18650.
Great idea with the screw. This is how i started with electronics a few years ago trying to convert these string lights to lithium. I first just solderd a USB connector onto it but that eventually burned out the LEDs that were expecting 2xaa batteries not 5v so i soldered a vape pen battery with a little bms that worked well between its 4.2 and 3v range,but wasnt satisfied with the capacity. So I switched to more in parrallel as well ,but for the 3xaa light strings I went back to the USB adapter which worked fine since 5v is close enough to 4.5v, and now you can hook up a power bank for even more light string capcity! Just cut a usb cord and hook the positive and negative to positive and negative in the box. I have like 6 strings going right now ,some on rechargable nimh and the rest on lithium usb packs, all charged from solar from today.
Don't forget, with the 6 cell flashlight modification, you must be mindful to now place all the batteries in the same direction, as shown in the first parallel modification or you will short out the batteries. You might also have to add a nipple or build up the negative terminal on 2 batteries to make a connection to the previously positive terminals in the holder, but that will depend on if the holder has recessed (previously positive) terminals.
Also, state of charge could become an issue. Placing a random handful of cells in parallel would result in completely unregulated equalization current flowing which could get hairy.
One neat trick is to use a spacer and run those 3AAA flashlights with a single AA or 18560 battery. The LEDs cut out when the battery drops too low, a little less than 3V. A little lower than ideal but if you save the lithium ions out of stuff this is ok.
For the parallel conversion: would have much better to adjust the *device's* contact in the middle, with a spring, instead of making the middle batter 'special'... now that battery is specific purpose. Instead, modify the little contact inside the case with some solder or a piece of nickel strip with the spot welder! This way all your batteries are equivalent and interchagable.
*Thanks!* Battery capacity, hours, & charging specific types has always confused me, this didn't as much. ... so there's hope. Now to retain info so i may Try. Great info below in comments, too.
instead of using a bolt just ground out one of those dead AA batteries. color it or wrap it so u can quickly know its a blank ... yup ground out=solder the negative terminal to the case caz its really close. or in a pinch just wrap it w/ foil / strip it 1st if u wish
Good video. I'll check out the 14500. However, my question is: Why would the manufacturer create a AA battery equivalent in size but maintain an 18650 battery voltage of around 4 volts? People might forget this and add to many batteries in their appliances with dire consequences to those appliances. Like nimh or nicd batteries which are great as a rechargeable, these should also be 1.50 or 1.25 volts. Conclusion: My thinking is that the manufacturer will use these 14500 as a future replacement for the 18650 li battery as the 14500 uses less materials and yet maintains 4. 20volts. However, capacity is sacrificed.
AA battery holders for use in projects are more common than 18650 battery holders. For small size or low power applications, AA size is smaller and lighter.
Do not do this if you plan on recharging your lithium cells. Many electronics that take alkaline cells do not have a low voltage cutoff and you run the risk of discharging your li ion too much, which will cause damage to the cells and cannot be safely recharged.
Thank you for your content. It seems you are fairly up on this area, so it makes me think my understanding is lacking. I currently use AA LiIon batteries for all the benefits you mentioned. Is the benefit of a LiIon 14500 over AA cost or availability where you are? Certainly the convenience of using the specified number of batteries in each device is a big time savings over the amount of time taken to jury rig voltage adaptations.
No benefit, but some of the 1-1 Li-Ion replacements for AA batteries have issues. I've tried a fair few. The problem with many (but not all) of these is that the little charging and voltage regulation circuit they put in these causes the battery to drain even when not in use. Not much of an issue in applications where you charge the battery and then use it till empty, like R/C cars, battery powered toys and so on. But it's an issue if you want to be able to grab a fully charged battery from a drawer where it has been sitting for months. Or in low-power, long-endurance applications, such as in remote controls or smart home devices.
@@kaasmeester5903 For what it's worth, I'm using Hixon brand. Haven't tracked discharge when not using, but rarely used devices powered by these AA batteries seem to go on forever. Certainly not a double blind study but...
I harvest little Li-Ion batteries from old used vape cartridges and solder into some devices and hobby JST male/female wires leaving terminal exposed just wrapped with tape so they work in my Li-Ion charger with tape off. If you have a device that uses a 3 slot AAA battery cartridge and it is configured in series such as in many flashlights the cartridge is the same size as an 18650 battery and the same voltage. I have done this on many flashlights for years. I also buy 18650 cartridges aka battery holders with flying leads and mount them external to devices that use 3 AAA batteries and solder the leads to the positive most and negative most terminal and put a notch in the battery cover for the wires to pass through. If you are creative and it doesn't effect the look or performance of the device I either glue or attach with wire ties the 18650 battery holder to the casing of the unit. I use many headlight flashlights that have a battery case on the back so I cant see it while using it and literally no issue with function unless I bump the back of my head really hard. If you are creative 26650 batteries can replace C size batteries.
In American prisons, we drop the battery on concrete floors. If it bounces, it's dead. It just plops, it's good. Worked well when there was no other way of testing. The old gum wrapper and battery trick works well for a lighter, also 😂
Try using a 3 volt lithium battery in a device that uses only one 1.5 volt battery. You just fried your device. If your device takes two AA batteries you will need to replace one battery with a dummy shorting cell otherwise you will fry your device when using two lithium’s which gives you six volts compared to three volts for two alkaline batteries.
Good Video. But let me tell you 0,5 v too much is enough to overheat and kill a lot of leds. I like the flexible 5v Cob Leds. They easily take up to 6v. The older Cob used in flashlights would die instantly directly connected to a lithium battery. I used resistor (p100) to solve this. And it was a lucky shot 😊 why so much afford? Any flashlight on my skateboard didn't work because too much vibrations.
If you are going to the trouble of rewiring the battery compartment from series to parallel, I think its prudent to rearrange the position of the negative terminal springs accordingly. Li-ion cells are much less forgiving than any other battery, when it comes to human error. When designing or building ANYTHING as a practical device, ALWAYS ASSUME the user knows nothing. It is an important part of the design process. I’d go to the extent of designing a label: WARNING This device have been modified to use 14500 Li-ion AA cells ONLY. Incorrect loading of cells will create RISK OF FIRE. Do not allow DEVICE to recharge cells.
Unfortunately alkaline batteries probably wont be going anywhere anytime soon. It is a lucrative scam. Most devices that use them quit when cell voltage is still around 1V. That translates to less than half it's energy content being used. Realistically they should have been banned long ago.
I totally agree with you and add one more thing to that. Stop or ban AAA cells immediately because it doesn't hold much energy compared to their environmental footprint from manufacture to disposal. I use the 1V batteries in my computer mouse which has a boost converter that will run until the battery is completely exhausted or on quartz clocks.
