LiIon Battery Shelf Life?

"How to Prolong Lithium-based Batteries" Basically, store them at about 50% charge and not in any place that gets hot.

My cell phone is also an antique (LG VX8300). I also have several friends that use the same model phone. Batteries on eBay began to get scarce and finally disappeared about 2 years ago. Then, the reappeared on eBay claiming to be "new". So, I bought a few and found that some clever entrepreneur had printed new LG labels, and taped them over used batteries. Normally, I would have complained, but the batteries tested quite good on my discharge tester. We've been using them for the last year or so without any capacity, bulging, or explosion problems. So far, the stock LG batteries tend to last a little longer than the aftermarket clones.

Yet another source. No clue on quantity, availability, or quality:

We keep batteries in the meat section of our fridge, where it's very cold. I suppose freezing them would be even better.

Thanks, Jeff!

Can you recommend a stand-alone charger for BL-46CN? All I currently have are chargers that use the USB port and require the battery be in the phone, which is a nuisance for keeping a back-up battery charged. ...Jim Thompson

I have been freezing a couple of Li-Ion batteries that are spares. This seems to slow down the ageing process, other wise it's about 3 yrs. And try to keep the battery between 25% and 75% charged, that also slows down the aging process.

Cheers

In a former job, we had to use a custom LiIon battery (they pretty much all are) but we didn't sell many units a year, at least at first. As a result, the batteries sat on the shelf for quite some time. We tested a 3 year-old batch and they were still within spec. They'd been stored in their original boxes on a warehouse shelf. No particular care, other than it probably never got over 85F and never close to freezing.

That works for most battery chemistries. However, the problems begin if you remove the batteries from the fridge/freezer, and immediately use or charge them. What happens next varies by battery chemistry. Quality LiIon chargers have an under temperature sensor, but that does little good if the temp sensor is in the room temperature charger, while the battery is still frozen from being quickly removed from the freezer. Unpackaged and unprotected cells, such as most flashlight batteries and model car/plane/copter batteries have the temp sensor in the charger, which means the cells must be brought up to (balance) charger temperature very carefully and not accelerated in an oven. Packaged batteries, such as cell phones and laptops, have sensors inside the pack, and are expected to be charged where the battery and charger temperatures are different.

It's probably safe to freeze your batteries, but please take the time to bring them up to room temperatures before charging or using.

"Many battery users are unaware that consumer-grade lithium-ion

appears to be charging normally, plating of metallic lithium can occur on the anode during a sub-freezing charge. This is permanent and cannot be removed with cycling. Batteries with lithium plating are more vulnerable to failure if exposed to vibration or other stressful conditions."

It is my understanding that cooling and freezing will reduce the chemical reaction rate of a LiIon battery sufficiently to allow storage at full charge for extended periods. I have not tested this to see if it really works. Just don't try to use or charge the battery when cold.

Yep.

I keep a few mostly charged LG batteries for my phone in my car. They get hot, they get cold, and they get banged around, but are usable when needed. I recharge them every 3 to 6 months. For self discharge rate, see Fig 3 below:

For vehicle storage, I suggest some insulating tape over the contacts or individual plastic bags per cell to prevent shorts. Any cell that appears to be bulging should be recycled. Or, you could use the Dreamliner 787 "solution" and put your backup batteries inside a ventilated fire proof steel box.

Excuse my ignorance, but what spacing do you set the pins since the BL-46CN battery has four contacts?

...Jim Thompson

You'll need to be creative with the contact arrangement. I use various pogo-pins for the purpose: Drill two holes with the proper spacing into a plastic insulator. Hot melt glue in place or use the sockets. Attach charger.

For the correct connections and spacing, look for the + and - markings on the battery case:

In theory, you only need a connection to the + and - terminals. However, some batteries have protection circuitry designed to go open circuit if it detects an excessive voltage that might cause a melt-down. I don't believe that these LG batteries have that feature so you should be ok with this trick. Also, if you look carefully at the various external chargers shown in the eBay search, you'll notice that they all only have two contacts, not four, so it should work.