[dugggggg]

I bought the $13.50 charging pod on clearance at Staples about a month ago. Glad I only paid $13.50, as it has not been very reliable. As others here have also reported, I would often get the "lightning bolt" charging symbol but no actual charge.

I later bought the Battery Guru app, which has the cool feature of indicating both the charger type (which is responsible for displaying the lightning bolt) as well as the word "Charge". Finally, I could fiddle with the thing until it would seat properly and actually charge.

This morning I was reading about other users lamenting about the same thing, so I got off my duff and decided it was time to take a close look.

In one sitting, I inserted and removed my PB fifty times, using Battery Guru to indicate whether the seating was successful (27 times) or unsuccessful (23 times). Of the 23 unsuccessful attempts, 3 even failed to register the lightning bolt.

The high-current magnetic charge connector consists of three pins. On the PB, they appear to be made of stainless steel. On the pod, much softer brass. This choice of metals makes sense from a durability standpoint---much better for the less expensive pod to wear out first. The pod's pins are spring loaded to minimize wear and maximize contact.

The choice of metals also determines which will corrode. When dissimilar metals are in contact, all it takes is some moisture in the air and some electricity to start the oxidation process. Metals are ranked on the "galvanic series" by their respective electronegativities. Interestingly, all the corrosion occurs on the less "noble" metal---in this case, the brass.

Indeed, the PB's connector was spotless, but the pod's connector was tarnished and pitted. I used a center punch to mechanically remove the corrosion. Afterward the success rate increased to about 75%---still way unacceptable.

Someone suggested resoldering, but I feel that's a bit extreme at this point. So I'm planning on first trying two things:

1. Caig DeOxit. This is a chemical that you apply to electrical contacts to remove corrosion. I don't have any right now, but I'll be adding a $7 tube of the stuff to my next order from amazon.com.

2. Sacrificial anode. One clever way to remove corrosion---commonly employed in water tanks and automobile radiators---is to introduce an even less nobler metal into the circuit. This again forces all the corrosion onto that metal, which is eventually discarded. Normally such "sacrificial anodes" exist in a liquid electrolyte, but my idea is to simply fashion some aluminum pins hooked to some resistors, which I will plug into the pod when it's not in use. In theory, any corrosion on the brass will be magically drawn to the less noble aluminum. We'll see if we get bright shiny brass as a result.

[gadgetier]

having come from an engineering background, your prognosis makes peract sense! unfortunate that the manufactures didnt think about it !
Over the years ive owned some high end audio visual equipment and have periodcally seperated the cable connectors and cleaned off the built up gum/tarnish that had collected.

[Branta]

Stainless steel seems to be an unlikely material for the PB contacts. Typically it will form a (very thin) surface oxide layer which has a relatively high contact resistance, and it is usually difficult to make connections to other metals (like copper based tracks on a PCB) except by spot welding or screw fixing. Plated brass would be more likely, with nickel as one of the most likely plating metals.

From your description it sounds more likely you have a poor mechanical and electrical contact which is tending to arc and create pitting. Even a smooth contact face with an oxide layer will have enough resistance to cause problems. An irregular contact face will cause small contact area(s) and increasing contact resistance. This could become a vicious circle with poor contact leading to arcing and even more irregularity or higher contact resistance.

[jeffgp]

i bought the rim charging dock for close to 50 .. and that would explain why having it sit on the charger for about 8 hours i picked it off the charger and it was at 65% ...

[dugggggg]

Stainless steel seems to be an unlikely material for the PB contacts. Typically it will form a (very thin) surface oxide layer which has a relatively high contact resistance, and it is usually difficult to make connections to other metals (like copper based tracks on a PCB) except by spot welding or screw fixing. Plated brass would be more likely, with nickel as one of the most likely plating metals.

I too suspected nickel plating at first---but it's more anodic than brass, so the corrosion should have occurred on the PB, not on the pod. So I quickly ruled it out and jumped to stainless steel based on its relative nobility, durability, and lack of magnetic conductance.

However, I now see cupro-nickel as another possible candidate---unfortunately I'm not at all familiar with it.

[FF22]

My BS-Biology head is spinning!

I tend to think that it is just poor contact. Do any of the three pins sit lower than the others? I have the rapid charger and otterbox (I am boringly repeating this). If the wire runs to the right, I get an angled connection and the Lightning Bolt but NO charge. Runing wire left generally results in a complete contact and charging.

Here's a picture of the issue on mine:

[spike12]

Stainless steel seems to be an unlikely material for the PB contacts. Typically it will form a (very thin) surface oxide layer which has a relatively high contact resistance, and it is usually difficult to make connections to other metals (like copper based tracks on a PCB) except by spot welding or screw fixing. Plated brass would be more likely, with nickel as one of the most likely plating metals.

From your description it sounds more likely you have a poor mechanical and electrical contact which is tending to arc and create pitting. Even a smooth contact face with an oxide layer will have enough resistance to cause problems. An irregular contact face will cause small contact area(s) and increasing contact resistance. This could become a vicious circle with poor contact leading to arcing and even more irregularity or higher contact resistance.

Great insights.. I'm just curious are you a material scientist or engineer?

[peter9477]

Note that the effect of things like corrosion and dirt is made worse by the pins not having a good solid contact.

The underlying problem, in most cases, is almost certainly that the pins simply aren't pushed together enough, caused by a poor mechanical design. This poor design allows too many possibilities for problems to creep in, be they weak or defective springs, the pins "sticking" inside their shafts, dirt, dust, or corrosion coating the surface, a slight misalignment of the connectors leading to one pin being slightly too far to make good contact, or a manufacturing/build problem (as in mine and I'm sure many others) where one pin simply starts off too low and cannot make good contact.

I actually did a careful measurement, accurate to probably better than a half millimetre, and concluded that with my cradle, the one pin simply could not make a proper contact with its mate. At best it was only just touching, with no spring pressure behind it. This led to mine being flaky from day one, and growing worse over time due to either the dirt/corrosion effect, or some slight weakening of the spring, or both.

[drudometkin]

So basically it is very poorly designed. Cant believe I paid so much for this junk accessory.

[farskija]

I agree with Peter9477 above. When I look at my charging pod the left-most pin appears "lower" or more sunken in than the other two. So far I have only had one time when my pb didn't charge at all on the pod.

edit: i am not disagreeing with the metal analysis, i just noticed the difference in the pin height.

[dugggggg]

Thanks guys... I decided to test the "poor contact theory" just now, by employing a decidedly low-tech solution: using a square file, I filed down the track in the pod in which the PB sits. Enough to take off the glossy finish and expose some grayer plastic underneath. This made the PB ride a tad lower and the connector seat more deeply.

I then repeated half of my original Battery Guru seat test. After 25 successful seatings in a row, I can declare the problem ostensibly solved!!! The real test is if I can get a month or more of normal charges without having to fiddle with it 50% of the time.

[rustmonkey]

I bought the $13.50 charging pod on clearance at Staples about a month ago. Glad I only paid $13.50, as it has not been very reliable. As others here have also reported, I would often get the "lightning bolt" charging symbol but no actual charge.

I later bought the Battery Guru app, which has the cool feature of indicating both the charger type (which is responsible for displaying the lightning bolt) as well as the word "Charge". Finally, I could fiddle with the thing until it would seat properly and actually charge.

This morning I was reading about other users lamenting about the same thing, so I got off my duff and decided it was time to take a close look.

In one sitting, I inserted and removed my PB fifty times, using Battery Guru to indicate whether the seating was successful (27 times) or unsuccessful (23 times). Of the 23 unsuccessful attempts, 3 even failed to register the lightning bolt.

The high-current magnetic charge connector consists of three pins. On the PB, they appear to be made of stainless steel. On the pod, much softer brass. This choice of metals makes sense from a durability standpoint---much better for the less expensive pod to wear out first. The pod's pins are spring loaded to minimize wear and maximize contact.

The choice of metals also determines which will corrode. When dissimilar metals are in contact, all it takes is some moisture in the air and some electricity to start the oxidation process. Metals are ranked on the "galvanic series" by their respective electronegativities. Interestingly, all the corrosion occurs on the less "noble" metal---in this case, the brass.

Indeed, the PB's connector was spotless, but the pod's connector was tarnished and pitted. I used a center punch to mechanically remove the corrosion. Afterward the success rate increased to about 75%---still way unacceptable.

Someone suggested resoldering, but I feel that's a bit extreme at this point. So I'm planning on first trying two things:

1. Caig DeOxit. This is a chemical that you apply to electrical contacts to remove corrosion. I don't have any right now, but I'll be adding a $7 tube of the stuff to my next order from amazon.com.

2. Sacrificial anode. One clever way to remove corrosion---commonly employed in water tanks and automobile radiators---is to introduce an even less nobler metal into the circuit. This again forces all the corrosion onto that metal, which is eventually discarded. Normally such "sacrificial anodes" exist in a liquid electrolyte, but my idea is to simply fashion some aluminum pins hooked to some resistors, which I will plug into the pod when it's not in use. In theory, any corrosion on the brass will be magically drawn to the less noble aluminum. We'll see if we get bright shiny brass as a result.

I had the same problem... Cleaned both the Playbook and the charger with 90 percent alcohol and now it charges at full voltage 100 percent of the time... Might just need a regular cleaning.

[peter9477]

I then repeated half of my original Battery Guru seat test. After 25 successful seatings in a row, I can declare the problem ostensibly solved!!! The real test is if I can get a month or more of normal charges without having to fiddle with it 50% of the time.

Great job, duggggggggg!

Do you happen to have a micrometer or caliper that can make an accurate measure of exactly how much material you removed? I bet it took only about 0.020" or so.

So we've got one electrical (resoldering) and one mechanical (filing) solution.

Calling all chemical engineers! Time to strut your stuff here and show us what you're made of here. ;-)

[Spencerdl]

Thanks for everyones explanation. Soooo since I'm not a engineer, am I to understand that the main problem is the metal that was chosen for the connectors on the rapid charging pod itself was a wrong. Now, how do I correct this $70 problem (the cost in May). Right now the pod just sits there laughing at me.

[ALToronto]

Back to the composition of the contacts. Wouldn't one of the sets be a rare earth magnet? And they do corrode very readily.

[peter9477]

The magnet's built into the connector on the PlayBook side, but it's not the pins themselves. The magnet's not involved in this issue.

[Spencerdl]

The magnet's built into the connector on the PlayBook side, but it's not the pins themselves. The magnet's not involved in this issue.

What is your best solution for the pod problem?

[dugggggg]

I have been playing with my newly filed charging pod and am really enjoying the improved reliability. It feels kinda like NASA fixing the Hubble after it was launched

Unfortunately, there is still sometimes a problem---I am now noticing that the pod's plastic connector can wiggle forward and back a small amount, due to the connector sitting in a slightly larger opening in the pod's case. If the connector wiggles forward too much, engagement becomes difficult and unreliable. I'm not sure if this problem was exacerbated by the filing---or it was always there before.

Therefore, BEFORE FILING, try this simple fix first: insert a tiny, thin piece of rigid plastic or cardboard into the opening on the front side of the connector. You may need tweezers. This should push the connector toward the rear and inhibit the wiggling.

[FF22]

Thanks for everyones explanation. Soooo since I'm not a engineer, am I to understand that the main problem is the metal that was chosen for the connectors on the rapid charging pod itself was a wrong. Now, how do I correct this $70 problem (the cost in May). Right now the pod just sits there laughing at me.

I think the filing option sounds pretty reasonable. Lowering the pb in the slot should allow better overall contact on those spring loaded pins.

I think the major flaw is the false Lightning Bolt which provides this sense of security which is actually absent. It can be triggered by only two pins contacting the pb but NO charging occurring.

[FF22]

The magnet's built into the connector on the PlayBook side, but it's not the pins themselves. The magnet's not involved in this issue.

Ah, interesting. I did not consider which side the magnet was on and for some reason thought the plug was the magnetic part but it is the pb socket. Not that it matters as I knew the issue was the pins not making contact.

[willtothewong]

Just when I thought picking up the charging pod would be a very nice and easy charging solution...hehe

[FF22]

I think the rapid charger (not dock/pod) is generally easier to tweak and get a good connection with than the pod/dock. The small magnetic plug (well, the pb is the magnet) is much easier to seat as you can more easily see what's what. As I've written before, I've done it in a dark room without looking - the plug generally homes right into the socket.

[cntrydncr223]

My charging doc seems to work fine, but my PB only charges to 99%.
I think I read somewhere that that is an issue with the reding gauge or malfunciotn of the numbers on the battery, was that correct?
TIA

[peter9477]

Unfortunately, there is still sometimes a problem---I am now noticing that the pod's plastic connector can wiggle forward and back a small amount, due to the connector sitting in a slightly larger opening in the pod's case. If the connector wiggles forward too much, engagement becomes difficult and unreliable. I'm not sure if this problem was exacerbated by the filing---or it was always there before.

The "problem" was there from before. It's actually clear from what you can see if you disassemble the unit that it's an intentional design. The connector is "floating", slightly, so that the two sides will more easily mate.

In general it should be a good thing, since otherwise everything is very rigid and you'd have to be excessively precise in aligning things as you plug it in.

In practice, I could well imagine that, especially with a modification, this will work against things a bit and make it slightly less reliable (in mating) than it would be without that feature.

[peter9477]

Just when I thought picking up the charging pod would be a very nice and easy charging solution...hehe

Actually it's a perfectly effective solution, in my view, provided you can inspect the plug and confirm all three pins are at identical heights.

It may take a trained eye to tell the difference, unfortunately. If you can notice it in F2's photos from earlier, or mine (in another thread but linked above, I believe), you'll probably be able to notice it in a store, if you could get anyone in the store to let you open the box before purchasing it.

For $13.50 they might not, but if you're paying full price you should definitely demand this or refuse the purchase, in my opinion. We don't really have any data on what percentage are defective, but I wouldn't be surprised if 50% of them have a latent problem, and people who buy them just think it's flaky ('cause it is) and keep using it, or just stop using it and don't complain because that's how many people are...