MyMPx.org - Placing a new battery

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Quote:

Originally Posted by lattesurf";p=&quot (Post 23062)

gbakakos , for trickle charge, the charge rate should be at 0.1C or 100mA. The USB port should be alright, but not on the AC adaptor. Since the AC adaptor supplies 1A which is 1C, the trickle charge current is too high.

Besides, there are no safety cut off sensors in the AC adaptor. So the adaptor would continue supplying 1A even when the battery has charged fully. This 1A is what causes battery damage when it is over-charged.

These players are cheap goods, so you can't expect sophisticated features like cut-off/temperature sensors in the chargers, as what all brand-name players or rechargeable batteries/chargers have.

So basically, when it's charged full, unplug your player. Trickle charging for extended periods isin't good for the battery either.

Yes, but arent there overcharging IC sensors in the batteries themselves? At least the good ones. I posted a link here (in the OTHER thread on this issue) to an EBay seller that is selling a quality product with overcharging IC's. And if there's still a risk with overcharging ICs, I'm wondering if you can get a brand name charger that will work in charging these players? (It woiuld have to accept a standard usb cable at least)

(Relikk: Check out that eBay link in my other post. Not all lithium batteries are created equal! The battery he is selling uses Japanese cells (but assembled in China no doubt), and not the cheap CHinese cells that have a greater reputation for swelling).

michiganjfrog , in general the cheap replacement batteries don't have much IC protection within it. Even those that do, i guess it would pretty much be at the very minimal.

The Japanese cells you mentioned might be of the higher quality, and probably contains better IC protection to cut the charging current off when full.

It is possible to use brand-name lithium chargers, but not very practical in these players. They don't come cheap, around the range of $70-$150. And you will need to remove the battery to slot into the charger itself, just like charging AA/AAA in wall socket chargers. As these chargers uses temperature sensors in addition to voltage sensors to sense the capacity state of the battery.

But normal charge via AC or USB with the cheap batteries would be fine. Just keep the overcharge time as minimum as possible, and you'll avoid the battery swelling.

Re: Placing a new battery

Quote:

Originally Posted by lattesurf";p=&quot (Post 23062)

That's not always possible, though. You might start charging, then you have to go out in a rush, youi forget youre charging your player. Next thing you know, you come back, your house has burned down! That may be a bit extreme, but Ive seen the youtube video of what could happen when you overcharge a lithium battery... pretty scary. Its not just chemicals melting keyboards but fire that could catch and spread. So it people are going to use these cheap AC chargers to charge their battery, it is good advice in any case to have a good quality battery and not overcharge it.