Talk:Battery Charging

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Battery theft?

Battery-2.jpg

I've seen that everybody has direct access to the battery pack. I suppose that there is no lock or something like that to deter a person to take away this battery pack or to substitute it with normal batteries. That could be very possible, since the OLPC batteries are very special ones, even unique. Because of that there could be a market for those unique batteries.

Another possibility: One child in a classroom gets after two years a new battery pack because his prior battery pack is damaged. The new pack has a higher capacity ain comparison to the others in class. So it is very possible that the other classmates realizes that and perhaps a quorral starts. It could even be possible that one classmate exchanges his old pack with lesser capacity with the new one with higher capacity, if there isn't an obvious sign that stands for the new pack.

You offer for identification serial numbers on the battery pack. Is this obvious enough so that a young child can easily identify his battery pack? Does OLPC offer some additional solutions?

Perhaps I've got a solution. You write a program that bundles one battery pack only with one XO-laptop. If a new battery pack with a different serial number is inserted the computer should stop using this battery pack. Only after confirmation by a teacher it should work together.

I think your solution would go against the idea of sharing.
Besides, the simplest solution is to grab a permanent marker and write the name (or some other identification) on the battery—you can use the underside if you want to keep the laptop 'clean'. Locking laptop-with-battery is setting up a police (via software) for a problem that may not occur, so why spend energy making a rigid system, when the objective is liberty? --Xavi 10:34, 3 June 2007 (EDT)
Yes, thats true. Writing the name on the battery with a marker should work with young children. But the real problem lies in the potential market. The project will afaik use LiFePo4 batteries. These batteries will have a certain value, because this type is brand new and they have an extraordinary lifetime (4 times longer as the standard, as OLPC writes in the wiki). So there can be a demand for these batteries. What is the fair price for these batteries? I don't really know the price, probably 3 USD each, 12 USD in total? So there is probably an offer from a poor familiy. Probably they need some money very urgent or perhaps they don't realize the importance of education. For the western world 12 USD are nothing but e.g. in Nigeria that's perhaps the weekly income or more.
And if a poor familiy doesn't want to sell the batteries, it is possible that these batteries are depredated on the street. Especially when young, 10 year old kids, who are not able to defend their property effectively, are living in a poor housing area. If the batteries are gone your complete concept of mobility and computing everywhere doesn't work like you are planning. Even if these kids have a small generator they can't store the energy because the batteries are gone. Computing will be restricted to school or other places where acceptable infrastructure, a grid exists.
In my opinion there is a risk in your concept. You have developed a good anti-theft system for the laptop but afaik you have excluded the energy system from this or another anti-theft system. But the energy system is crucial for your learning concept. Without the batteries your laptop is bound to cities or electrified villages. It is no longer usable in the outback.
Of course, the idea if sharing is especially for an Open Source project of high importance. But sharing is something different than being urged to give away, for whatever reason. It's possible that I emphasize these risks too much, probably no market for LiFePo4 batteries will come into existence. But even if the OLPC project does think so, it would be in my opinion sensible to have a backup plan, if this will happen in some countries.
As I said before, for young children it's enough to mark the battery pack with a marker, but every marker is non permanent. Either a marker is water soluble or it can be wiped off with alcohol or benzine. For a professional trader that is not really a huge barrier, isn't it?

Disabling the mesh network

Another problem: You don't want the children to disable the wireless mesh function. Therefore it is not possible to shut down the built in router by software. But I suppose that time by time some children realize that they can save power by unplugging the whole battery pack if they are not using the XO for writing or chatting, etc.

For this problem I don't have a solution. Does OLPC have? A suggestion: One solution could be to write a program that measures how long the laptop was online for supporting the mesh. If it was to little online it should request the user to support the mesh for a longer time.