A higher wattage adapter can charge anything with the same or lower wattage. For example, a 65 watt adapter can charge a 65 watt notebook or a 40 watt notebook. A 90 watt adapter can charge a 90 watt notebook, a 65 watt notebook, and a 40 watt notebook.
Ah stands for Amp Hour, a technical term for how much energy a battery will store. Batteries with higher Ah values are able to last longer between charges. The higher the number, the more energy a battery can store.
New Laptop Battery Calibration. If your new battery charges but does not charge to 100% or stops charging each time your charge indicator reaches 85-99%, you may need to recalibrate your laptop for the new battery. This occurs often when replacing an old battery with a new battery. The laptop has to adjust itself to get used to the new battery. In order to recalibrate properly, you will need to set the Windows power management so the laptop does not go into standby or hibernation when the battery gets low. Instructions: With Windows XP, navigate to Control Panel > Performance and Maintenance > Power Options. Set "Power Schemes" to "Always On". Under "Alarms", uncheck "Low battery alarm" and "Critical battery alarm". Under "Hibernate", uncheck "Enable hibernation", then click on Apply. With Windows Vista, navigate to Control Panel > Performance and Maintenance > Power Options Click "Change Plan Settings". Set all tabs to "Never" underneath "On Battery" column. Click "Change advanced power settings". Set Sleep > Hibernate after to 0 or Never. Set Battery > Critical Battery Level to 0. Click on "OK", then "Save Changes". This is the only time that we recommend taking the battery all the way down to zero percent. Unplug the ac adapter, and let the battery drain all the way down until the laptop shuts off. Then plug the AC adapter back in, and let it recharge to 100%. You may need to repeat the cycle 2-3 times before it actually reaches 100%.
mAh stands for Milliamp Hour, a technical term for how much energy a battery will store. Batteries with higher mAh values are able to last longer between charges. The higher the number, the more energy a battery can store.
To be kept on a charge continuously a "float" charge is needed. A float charger will deliver a lower voltage charge (2-v range) consistently and will can help keep a SLA battery in good working condition for long periods of time.
At a full 12-14v charge, the charger needs to be removed as soon as the battery is charged or the plates can become corroded and a battery can be ruined in days or weeks. Unregulated Transformer-Based Chargers, should be removed right away after a full charge is achieved.
For a float charge a more sophisticated charger is needed. If a unit is being unused for an extended period of time it should be stored in a cool place with a float charge on it. Otherwise the charge of the battery should be constantly monitored, making sure it is never fully discharged, and charged periodically with the charger being removed as soon as a full charge is reached.
If maintained properly a sealed lead acid battery will last up to 5 years. However just one extended discharge can render an SLA battery useless. Even a near deep discharge can greatly reduce the amount of charge a battery will ever be able to retain. An SLA should never be fully discharged, as the battery does not need to be periodically discharged in order to maintain its performance, in fact, it is best kept in a fully charged state at all times. SLA batteries can also be damaged by overcharging. A charger should be removed as soon as the battery has reached its full charge. They should be stored in a cool place when not in use, and can be damaged if stored in a hot area for an extended period of time.