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Question:
I am a parent. As such, there is an unfortunate abundance of toys and gadgets that consume no end of LR44 and CR2032 batteries, and it pains me to use disposable batteries.
I have been unable to find any vendors of rechargeable alternatives. I have found plenty of questions that are answered either by “if they were rechargeable, they wouldn’t be named LR” (correct, but unhelpful) or by sales listings of “non rechargeable” batteries (dumb search engine). I did find one vendor, but needing to send an inquiry to receive a quote sounds decidedly not consumer oriented so I haven’t even tried (I’d need, say, 30 button cells at most).
So, if I would like to replace current LR44 and CR2032 batteries with rechargeable alternatives … what are my options? And just as crucial: I’d also need a charger!
…
Alternatively: why do such options not exist?? In spite of my household, is there really no market for it?
Answer:
Rechargeable options do exist, but there are issues to consider.
For the 2032 coin cell, the rechargeable version uses a different chemistry. Its output is 3.7 V, while the disposable version produces about 2.9 V (mid-discharge cycle). There’s about a 50% chance the circuit in the toy will burn out with the higher voltage from the rechargeable. Also, the capacity of the rechargeable is about 25% of the capacity of the disposable, so if you’re having to replace the disposable once a month, you’d be having to recharge the rechargeable every week.
For the LR44 there’s a rechargeable version, with the opposite problem. The rechargeable chemistry (NiMH) puts out a lower voltage (1.2 vs 1.5). It probably won’t burn out the toy, but it may not work or produce weaker sound or light. And you have the same problem of only 25% capacity.
Rather than go rechargeable, you can buy the coin cells in sufficient bulk to make up for shipping costs, from a wholesaler (e.g. Digikey, Mouser). Store the unused cells in a cool place – but not where they might be mistaken for food! – to prolong the shelf life. Remove the batteries from toys not currently in favor. And save up the depleted batteries until you have enough to take them to a recycler (Home Depot, Batteries Plus, etc).