BP511 Battery Charging Problem

Hi there everyone... I'm hoping someone can help me out here...

I have several Canon-brand and generic BP511 batteries. I have two chargers, the original Canon-brand charger that came with my Canon 10D and a generic charger I purchased on ebay.

Problem is... some of the batteries (both brands) won't charge. They charge for 1-2 minutes then say they're done, but they're certainly not done charging. About half of my batteries work fine, I don't get it.

Anyone have any insight here?

-dave-

Check the contacts and make sure they are clean.
Also, you can use a voltmeter to see what the charge is. Sometimes you may need to manually discharge them by attaching a small light to drain it. Most chargers are smart and will see if there is a certain voltage, it will not continue (for safety). If you still have warranty, return them.

No no nooo ! Never, I mean never drain a battery empty by attaching a lamp bulb or any kind of "dumb" resistor to it : you'd destroy your battery pack for sure !

The only way to safely discharge a battery is to use a specialized discharger (some "smart" battery chargers can do that, too). The reason is that (electronics in) the camera will stop functioning under a certain voltage. Nevertheless, the battery is not really "empty" and if not properly drained from time to time it will develop a so-called "memory effect", preventing any further attempt of full re-charge and full dis-charge. Old-timers NiCd batteries are the most prone to this phenomenon, but more advanced ones still show this drawback.

Of course you could drain it down to zero volt using a lamp or a resistor, but this would destroy it because a NiCd, NiMH or Li-Ion cell must never fall under a certain voltage. In other words, pulled down to zero volt it dies (besides of that, there is a risk of fire by internal overheating, or even explosion).
That's the reason why various suppliers propose different battery dischargers to effectively and safely restore defective batteries back to a normal behaviour.

The second point is that a voltmeter will never tell you the level of charge (capacity) left in a battery : it will only show the level of tension (voltage) from which you cannot determine how long it can last ; advanced batteries like Li-On but also older Ni-XX still get a rather high voltage a long time, then it drops all at a sudden. Thus a voltage reading cannot help predicting the remaining life expectancy of a cell.

I don't intend to be rude but - for your batteries' sake - remember : this is not an opinion or an advice, this is a warning !

I agree with Pierrot. For many, it's just too risky and not worth the trouble.
There are those that even suggest Zapping "Jump Starting" the batteries but this is much more risky.
Get a proper discharger and since you have more batteries it is probably worth the investment.

That technique worked well, but only on some NiCd batteries about 25 years ago.

---Bob Gross---

Thanks for the advice, however, I'm having a lot of trouble finding a "smart" charger that is ACTUALLY smart (a lot of generic ones say they're smart simply because they have a light that tells you when it's done). Does anyone have any reccomendations?

Thanks,
dave

For a BP-511 type of battery, I cannot recommend anything specific that is much smarter than the Canon charger or a little 12-volt input version that I got from Greenbatteries.

For the vast majority of consumers these days, a rechargeable NiMH AA battery is the most heavily used, and there are several very intelligent chargers that monitor and charge each one of two or four independently of the others. If you get one weak battery in a set of four, that can screw up the performance of the whole set.

However, the battery issues are rather different between a BP-511 and a NiMH AA battery.

---Bob Gross---

http://store.yahoo.com …s-store/batterymyths.htm​l

There is no memory effect on rechargable batteries, low capacity is largely contributed to overcharging in poorly regulated chargers.