|NOTE: The contents of this page are not set in stone, and are subject to change!
This page is a draft in active flux ...
WORK IN PROGRESS
A car battery is a lead-acid battery that provides a nominal 12-volt (actually 12.6V) potential difference by serially connecting six cells that each produce about 2 to 2.1V each.
Depending on individual specs, these batteries must be charged at 13.2-14.4V.
Car batteries are comprised of different types of cells, but the XO will preferably need the deep cycle battery (DCB) type, for reasons outlined below.
Deep Cycle Batteries
The DCB's are designed to provide a steady amount of current over a long period of time; they achieve this by using thicker plates than typical car batteries. DCBs are found in boats, golf carts, toys, motorcycles and solar power systems. They are a class of car batteries in Africa.
Properties of batteries
- Cold Cranking Amps (CCA) - amps that the battery can produce at 0°C
- Reserve Capacity (RC) - minutes that the battery can deliver 25A, voltage > 10.5V
For DCBs, RC is 2-3 times greater than car batteries, while CCA is about 0.5-0.75 of car batteries. While car batteries are not designed to be completely discharged, DCBs should withstand hundreds of discharge/recharge cycles.
These are the launch countries; places where the XO's will be deployed first. We need to find information about the availability of DCBs in these areas.
As the OLPC organization deals with these countries primarily at a government level, we need to uncover local knowledge regarding sources of batteries, specifically regarding the availability of DCBs that are light enough for two children to carry. If you can help out in this area, please get in touch with Joel or Rafael
- Brazil (especially rural areas)
- Uruguay (especially rural areas)
- Argentina (especially rural areas)
This section should contain different specifications for DCBs and also availability in the different countries.
- http://www.laguarderia.com.ar/optima-batteries/optima_batteries_faq.php (Argentina)
- http://www.in-sumos.com.ar/listado.php?id_subcat=648&marca=TRV (Argentina)
- http://www.deremate.com.ar/accdb/viewItem.asp?IDI=15993677 (Argentina)
- http://energy.sourceguides.com/businesses/byP/batP/batt/byGeo/byC/Peru/Peru.shtml (Peru)
- http://energy.sourceguides.com/businesses/byP/batP/batt/byGeo/byC/Brazil/Brazil.shtml (Brasil)