Rechargeable 2032 key fob battery

I don't have experience with that product in a key fob but I would not expect any problem from the 0.6v difference.

I might consider the thought that the fob is built to be disassembled and snapped back together a few times, roughly tied to the expected life of the disposable cell. If you are popping yours open more often than that to charge the cell, you can potentially wear out the key in a different way.

 

I have not tried with coin batteries, but I have been using rechargeable lithium AA or AAA size batteries for many gadgets around the house. The thing is that for most low amp gadgets like remote controls, clocks, thermometers, Bluetooth temperature probes, etc, I find the rechargeable lithium batteries works fine but last shorter than regular alkaline or non-rechargeable lithium batteries. And for my application, the rechargeable batteries tend to drop voltage rather suddenly that one day it is working and not showing a low voltage indicator but the next day it is dead.

They work fine if frequent changing and sudden death are not problem. But for a car fob, I'd rather not have to change the battery often or be caught with a dead battery on the road. Regular CR2032 lasts a few years, and it shows a low battery warning on the dash when it is near the end of life. That's good enough for me. And saving... you are talking less than $1 every few years.

 

This is false economy.

First, the rechargeable typically have a slightly lower voltage and either won't work in some devices or don't run them very long.

Second, if a standard alkaline battery will last a year or more in a given device, you likely won't recover the initial cost of a rechargeable in 5 years or more......when the rechargeable might need to be replaced too.

Trying to find a rechargeable "button" battery for something like a car remote which in my experience might last 4 or 5 years, is just not a wise thing to be wasting your time on.

 

I see there are other rechargeable chemistries(ML & VL) that are 3V, but they seem to be used in devices with built in charging. If you happen to have some device that uses them, they can be an option, but accessing a computer's motherboard isn't exactly convenient.

Duck Tape now comes in a range of colors and patterns.

This comes down to how often the battery needs to be changed. If it's down to months from years, I might start worrying about it. The fob case is pretty tight to begin with to survive getting dropped in a puddle, or left in the mud for over a year, and possibly run over in that mud. So it will take a lot of opening to wear down the plastic to the point it doesn't hold.

Unless Toyota stopped giving you a mechanical key and lock to the door, a dead fob is a minor inconvenience. Once you have an idea on how long the rechargeable lasts, a schedule for putting in a fresh battery can be enacted.

The cash savings are slight, but the fact that there is some means it isn't a burden to do. Because there are other costs one can be concerned with. Like reducing input to the waste or recycling stream, or reducing the number of coin batteries out there for clueless kids to swallow, which is much worse than swallowing an actual coin.

 

I wouldn't assume that. I coincidentally just replaced my key fob battery because yesterday the car display said the battery was weak. I tested the battery on my battery tester and it tested good, well into the green on the tester. I replaced the battery anyway and that fixed the problem.

I think this was the first time (maybe second, can't remember) in five years I've had to replace the fob battery (these batteries last a long time), so I don't think it's worth going to a rechargeable battery anyway.

I try not to use the buttons on the fob to save the battery, just grab or touch the door handle to unlock or lock the car.

 

If the battery goes bad in the fob (like the spare one I have in my safe) or I take the battery out of the spare one and store it without a battery in it, will that cause the fob to lose what coding is stored in it and cease to function when I want to use it again?

 

Are you sure that rechargeable batteries you are using as alkaline replacements, are lithium, not NiMH?

 

Yep, rechargeable Lithium-ion AA and AAA batteries like these. I also have used NiMH. They are even worse.

 

no, it is semi permanent, and can only be changed/erased with programming

 

i can't think of any batteries i use that would be worth changing to rechargeable. they all last so long these days.
back when we had kids, we used to burn through them regularly in toys, but the household stuff runs for years.

 

Just make very clear to potential adopters that these lithium rechargeables are 1.5V. They shouldn't inadvertently acquire 3.2V or 3.6V AA rechargeables like these:

1 Card: 4pcs Tenergy 3.2V 400mAh 14500 AA Size LiFePO4 Rechargeable Batteries - Walmart.com

Tenergy 14500 3.6V 750mAh Li-Ion Rechargeable Battery - Tenergy

I haven't used the 1.5V lithiums, but acquired samples of the 3.2V version to test for a certain project proposal. Now they have been reassigned to some single cell flashlights built to handle the full 1.5-3.6V range.

 

I think AA and AAA 1.5v rechargeable Li-ion batteries are fairly new. I tried Ni-Cd and Ni-MH before but neither outperformed the brand-named alkaline battery for my use. I was hopeful that rechargeable Li-ion would work as good as non-rechargeable Li AA and AAA batteries, but so far I have found rechargeables don't outperform non-rechargeable Li batteries and they are maybe equal or slightly worse than regular alkaline for my use.

That being said, I have tried only one brand of rechargeable 1.5v rechargeable Li-ion batteries made in China so far. It may be that the brand I bought was of substandard quality. I know not all 18650 lithium batteries are the same, so certainly there must be a quality difference in 1.5v Li-ion batteries too.

 

After searching a bit, I'm wondering if those rechargeable Li-ion batteries are not really 1.5V chemistries. Rather, they seem likely to have 3+V internal chemistries, with an added switch mode power supply (SMPS) dropping it down to a well regulated 1.5V for output. I.e. almost the same proposal @tochatihu suggested a couple weeks ago, but with the SMPS mounted in the cell casing, not in the powered device:

Lithium -- for household batteries? | Page 2 | PriusChat
Lithium -- for household batteries? | Page 2 | PriusChat

 

I didn't read the comments by @fuzzy1 in another thread but just did. I realized his comment in that thread is exactly what I have experienced.

For the "high drain" device, the Ultimate Lithium non-rechargeable battery worked very well. The 1st generation insulin pump could operate only on an Ultimate Lithium non-rechargeable battery for a reasonable period. Since then, the pump has been replaced and is now a rechargeable internal lithium-ion battery. Similarly, for my use in weather station setup, The transponders worked fine with regular alkaline and expensive lithium non-rechargeable battery did not offer many benefits. But for the base station with an LED display, lithium non-rechargeable battery lasts longer.

With many household devices, I use AA or AAA size batteries, most of the devices that benefit from lithium chemistry-based battery has already moved to an internal rechargeable lithium-ion battery pack already. The insulin pump mentioned above is one, and the point-and-shoot digital camera is another. But I found some devices may be served better with alkaline batteries. Remote control and flashlights are the ones I like alkaline in them. They tend to last longer with alkaline and when the voltage starts to drop, the device still works but not as good. In an emergency, dim flash-light is often better than having suddenly dead light.

So, to sum up... again fuzzy1 commented the conclusion. But for the CR2032 button battery in the fob, I don't find the benefit of rechargeable Li battery.

 

NO.
It is "hard coded" and not dependent on the battery.

 

I think I have a rechargeable coin battery in a lighting timer I just installed. It has a non-replaceable 2032 battery to retain the programming when the power fails. An application like this is where these batteries will be very useful.

This lighting timer not only switches for daylight or standard time automatically, but also takes latitude and longitude for calculating when to switch outside lights on at sunset and off at sunrise without the need for a connected photocell sensor. $30. Fits into a standard single wall box. Amazing.

 

The way that Rechargeable Lithium-Ion 1.5V AA/AAA batteries work is that they use a 3.7V lithium battery and use an always-on circuit that drops the voltage down to 1.5V. The circuit can either be a simple resistor (generates heat and inefficient) or a switching circuit (switches on and off very quick so that the voltage seems like it's 1.5V, most modern electronics use this method as it is higher efficiently). Most likely it is the later (switching circuit) as your device suddenly stop's working because there is a protection circuit that breaks the connection when the internal li-ion drops do ~2V. Li-ion batteries are damaged when voltage drops below ~2V. These types of batteries also have a short shelf life before needing to be recharged due to the always-on circuit constantly draining the battery.

In your use cases, unless the gadget has issues with NiMH which are 1.2V, I would pick up LSD (Low-Self Discharge) NiMH like Enloopes or equivalents (some times marketed as Pre-Charged or Ready To Use). Make sure that the packaging states, batteries "Made in Japan" and avoid the ones made in China (chargers are still made in china...). Brands that rebadge LSD NiMH from Enloope include Duracell, Energizer, Sanyo, Panasonic, Private-Brand Ikea, and AmazonBasics. Probably others.

For low-draining devices like remotes and clock, Alkaline battery will last longer than rechargeables. For high-drain devices like cameras and flashes, rechargebles win. However, for cost savings in AA/AAA, rechargebles wins hands down. I use recharges in everything that takes them, yes, I change them out more often... like 6 months instead of a year for a clock but that's not really a big deal for me. I have a few devices that doesn't like the 1.2V NiMH so I stick with 1.5V alkaline.

Besides the cost savings, in my opinion, the biggest and best reason to use NiMH is that they don't leak unless the battery is defective, physically damaged, incorrect use, or so old that it's rusting the casing! In my collection of over 100 NiMH, none has leaked, I've only seen pictures.

Battery voltage is weird. There is the 'nominal' voltage (1.5V, 3.0V, 3.7V, 12V, etc.) and then actual voltage when measured. A fresh CR2032 3.0V is really ~3.3V, while a fresh Li-ion 2032 3.6V really ~4.2V. So, ~.9V difference, which I think is 127% more power?

Personally, I wouldn't try to save $50 (over the life of device ?) on the off chance that I would need to spend > $300. If it was a $50 device (like an Amazon Fire or Nvidia Shield remote), I would test....

Some 2023 rechargeable batteries (nominal voltage):

• ML2023 70mAh Lithium Manganese Dioxide with similar voltage to the CR2023 at 3.0V.
• LiR2023 or LR2023, most are 3.6V-3.7V but depending on the Lithium composition, can be between 3.2-3.9V (see below)
• ICR2032 60mAh Lithium cobalt oxide cell with a nominal voltage of 3.7V
  
• IFR2032 45mAh Lithium iron phosphate (LiFePO) with a nominal voltage of 3.2V

 

It is not recommended to use a LiR2032 rechargeable battery in place of a CR2032 non-rechargeable battery in your Gen 4/Prime key fob. The voltage of a LiR2032 is 3.6V while the voltage of a CR2032 is 3V, which means the LiR2032 battery may provide too much voltage to the key fob, potentially damaging it.

It's also important to note that the key fob is an electronic device that requires a specific type of battery in order to function properly. Using a battery that is not designed for the device can lead to poor performance or damage to the device. Additionally, most key fobs have a battery life of 2-3 years, so even if you swap the battery to rechargeable, the key fob itself would need to be replaced before the battery does.

It's best to stick with the recommended battery type for your key fob, CR2032, and dispose of them properly.