For as long as we can remember we’ve heard the old wives tale that you should not mix battery brands in the same device. Naturally, that did nothing to prevent us from doing it frequently. We've never had any problems before (or so we thought) so it had to be fasle, right? Well it turns out the answer might have you running to the drug store after work.
We’re sure the story is familiar. The batteries run out in your remote or wireless mouse suddenly and you’re scrambling to replenish them and in fact, it often comes down to temporarily “borrowing” batteries from another device to place in your other one. This can often lead to mixing and matching of battery brands. But is this bad for your device or even your safety?
A quick search will online will yield vastly different results between unofficial websites such as Yahoo! Answers. Some suggest it is perfectly fine while others caution against it vehemently. But digging further, we found an interesting bit of information from Duracell’s official FAQ on their website:
“Different batteries are designed for different purposes. Mixing a lithium battery with an alkaline battery will not improve device performance. In fact, it will reduce performance and may even damage your device or cause battery leakage or rupture.
As well, do not mix different battery brands within a device. Doing so will reduce overall performance and may also cause battery leakage or rupture. We recommend using the same type of batteries within a device.”
And not only do they recommend not mixing across brands but they caution even so far as to say that you should not mix old and new batteries as well. They recommend you buy all new batteries when it comes time to replace them. All of this sounded well and good but we've never had a problem with a battery leaking or anything but it got us thinking about the performance and welfare of our device. Have we been doing our tech a disservice by not matching battery types and brands? Are we missing out on longer lasting battery life and cutting our device's life short? It certainly is food for thought and we'll be buying a single battery type in bulk next time they're on sale and see if our battery life lasts any longer.
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Well, let's just get right down to it . . .
Apple doesn't want you to ever see the battery, and it's rechargeable so that's so green, you know?
That's why every year when Apple releases a new product or two, I make sure to buy it and throw away the old one.
Honestly though, mixing batteries can be a bad thing only because different batteries will have slightly different starting voltages and will have varying milliamp hours, so they will lose voltage and charge at different rates. This really isn't that big a deal. All it means is that you might not get the most out of one of the batteries, since it won't be able to pull all the weight on its own.
The only other issue I could see would be galvanic corrosion, but that's like . . . so unlikely since batteries are made to work in all sorts of devices.
It depends on the item. I probably would use the same brand of batteries in a camera, or such electronic device. However, I am sure if you mix the batteries in your remote, flashlight, etc it is not going to make a bit of difference.
You're using Yahoo Answers for your research now? I'm not sure a properly researched answer has ever been posted on that site.
Wait, so we are relying on what Duracell, a company that sells batteries, says to replace all of them if one dies?! Seriously? The best answer we can get here is from this surely unbiased source?
Q: Is It Safe to Mix Batteries?
A: We don't know, and we just wasted 5 min of your life pretending like we were going to actually tell you.
This site is starting to go down the same tube as Lifehacker. Perhaps it's time to delete the bookmark.
I, too, used to think this was "fasle".. but now I see mixing batteries can reduce the effectiveness of your spell-checker...
my understanding is that it is not the brand or type of battery that is the issue, it is the capacity and discharge rate that is the issue, which of course can be tied to the brand or type, so if you have a 2000mah battery paired with a 2300mah battery they will discharge at different rates, and can cause one or both to heat up and then discharge faster, then it kills both, this can cause leaking and expanding. Bottom line is dont do it.
@battlehark Haha! So funny. We need that question answered on this site. How is babby formed?
@Kaz. You crack me up. I love snarky comments.
Lifelong cheapskate says: Be very scared of deep-discount batteries. They are prone to leakage and will ruin your possessions. The two main guys, Sears, and astonishingly Dollar General batteries, work well. I've had no leak problems with any of them. On the other hand, Panasonic and the Save-A-Lot house brands are flashlight killers.