[Galaxy S III Accessories] RobtGarrett:
Avoid Imitations

Regarding counterfeit and third party manufactured Li-Ion batteries for portable devices, plese let me add a strong warning.

Lithium chemistry cells can react to mistreatment (and even to what you may think is perfectly normal treatment) by runaway overheating, outgassing, swelling, rupturing, venting with flame, and in the most extreme situations (such as being enclosed a tightly sealed enclosure) exploding.

OEMs typically employ a number of technical means to protect the user from injury or damage to their devices ( and the OEM from lawsuits). For batteries and battery packs, the most important means is additional protective circuitry that fits between the anode/cathode terminals of the cells and the "+" and "-" terminals on the battery or pack. The circuitry detects when the cells reach maximum safe charge, minimum safe discharge, maximum charging or discharging current and often determine whether the cells are operating within a safe temperature range. Even small batteries for phones incorporate extremely small circuit board assemblies installed in the top of the battery just beneath the terminal contacts.

Counterfeiter and third party manufacturers often don't care about your safety and only want to build the cheapest possible product. They leave out the protective circuitry, which can add a significant percentage to the total manufacturing cost. After all, the bare cell works perfectly well without the protection and no one knows the difference until the battery burns up inside your phone. Actually, third party cells may not work that well, either because careless manufacturing practices introduce contaminants intothe cells that reduce theor performance. It's entirely possible that the third partye didn't actually manufacture the cell but bought the rejects from the OEM that didn't meet the performance specifications.

Please do yourself a favor and don't be tempted by the lower price of a third party battery. The risks are simply too high, and the phone you save may be your own.

I hesitate to add my full credentials, but let me qualify my position. I work for an organization that promotes safety in electrical/electronic products and my current professional focus is on portable energy storage products and charging systems. I have more than 40 years experience in electrical engineering, research, design, manufacturing and testing. I have seen too many counterfeit, copy cat, and imitation batteries and chargers being sold in too many outlets to keep quiet when I read exchanges such as I've found here.

The best protection you have from imitations is to buy from an impeccable source. Apple has the right idea with its stores, but Apple's chargers and cables are among the most copied and counterfeited in the world because the company tries to keep its profit margin high. Their little1Ampere USB cube charger is one of the most copied I've seen and every fake is potentially dangerous to your iPhone or to you personally (Remember the young Asian woman who was electrocuted?). So, if you own an Apple product, your best choice to to buy from an Apple store.

I just bought a new Samsung battery and external charger for an S3 through Amazon. (I almost ordered it direct from Samsung online but I have a convenient relationship with Amazon when I believe that I can trust the product I buy from them.) While the charger and battery came packaged together inside a single Samsung retail carton, I will continue to be careful while I run some initial performance tests, but I feel fairly certain that the products are genuine. On the other hand, if I had bought a battery or charger that arrived in "bulk packaging," i.e., a plastic bag, I would be forced to assume that I just bought a bag of worms.

What I've said about batteries holds to chargers as well. There are many simple designs for circuits to deliver charge current to a battery, and most of them will do nicely if you are ready personally to measure the voltage on the battery periodically and check that the battery isn't overheating. A properly designed charger from a reliable source will perform all the necessary functions to monitor the battery and protect it (and you) from damage. The fake Apple chargers I noted become overloaded when connected to charge at their claimed 1 Ampere output. Their output voltage drops to as little as 2 volts instead of 5. They have no means to monitor the battery voltage and end the charging current when the battery is at full capacity (but why should they since they won't charge the battery completely anyway?). Likewise, many third party chargers/AC adaptors for tablets, notebooks, and laptops are notorious for overheating, melting, and even igniting during use. So why take the risk? Buy from a source you can absolutely trust, even if that means buying directly from a manufacturer or its authorized distributor, and pay the full price. In these situations, you will truly get what you pay for.

Of course, if you buy a less expensive third party device, you'll still get what you pay for. You may not like it.