For Advent 5421 6552 Battery U40-3S3700-B1Y1 Laptop New

1. UK STOCK. All items will be dispatched within 1 business day after receipt of payment via Royal Mail 1st Class service. It will takes 2-3 days for
    delivery for UK buyers. For buyers outside UK, normally it takes 5-7 working days, or even up to 15 working days for some countries, such as
    Portugal, Spain, Italy. But, The transit time is highly depended and provided by Postal Service, if you have any problem, please contact us.

2. Please NOTE that orders placed on weekends and public holidays will be despatched on the next working day.

We ship items to your Paypal confirmed address only. Please make sure your address in PayPal is matched with your shipping address before you pay.
We are unable to take any responsibility for wrong address, any custom delay or tax. Because transit time is highly depended and provided by Postal Service.

1. 12 months Warranty from the date of purchase covering manufacturing defects. This warranty excludes any damage caused by the user.

2. Returns must be made within 7 days of receipt of the product and in original packaging. We will refund you less the P&P. In order to process your
    return or exchange, please contact us first via eBay, supplying your eBay ID, item number, full name and the reason of returning.

3. Buyer has 7 days to inspect the product & report the manufacturing defect. After 7 days items can only be exchanged. Exchange shipping cost
    should go to buyers.

4. If the return is due to the mistakes of buyers, for example, wrong purchase, no need of the batteries after transaction, or other artificial damages,
    postage and handling cost would be deducted while refunding.

Adjust your laptop battery in order to achieve optimum performance.
Laptop battery has built-in microprocessor software, it can calculate the remaining capacity of a battery when it is charging or discharging. Battery needs to be adjusted from time to time to ensure that the screen displays the time and percentage is correct. You should implement a full charge and discharge operation at its first use, and thereafter every 2 or 3 months once the operation as follows,

1. First of the "Power" option setting: Right-click on a blank screen, then select "Properties" → "Screen Saver" → "Power" → "Power Schemes" →
    "Portable / Laptop". Then, select "Never" for all the options of the “Battery Schemes", and for the "Warning" options, don't choose "Low Batter
    alarm" or "serious shortage of battery alarm".

2. Disconnect the AC adapter and use your laptop until it itself shuts down. In this situation, the battery is fully discharged.

3. Connect the AC adapter and your battery should start charging. Charge until the battery is full. Repeat this charge and discharge cycle 3-4 times
    and your battery pack will be conditioned to perform at full capacity. The process of charging takes at least 5 hours or more.

Note: When your battery is adjusted to achieve optimum performance, please set your computer's power options to their default values to ensure that
           your computer can send the correct warning signal. Such as: low battery alarm or alarm before sleep and so on.

This battery which I just received isn't charging well, is it a defective battery?
New batteries are hard for the device to charge, as they have never been fully charged and therefore "unformed". Sometimes the device's charger will stop charging a new battery before it is fully charged. If this happens, please turn off the laptop and remove the battery from the device and then reinsert it. The charge cycle should begin again. This may happen several times during the first battery charge. However, if this doesn’t work,
please email us to confirm the problem. (Providing us the part# of your original battery and the model# of your device will be highly appreciated)

I have discharged the battery to zero volts, and fully discharge and fully charge as your instruction, but the battery can not charge to
100% capacity?
Our battery pack is made up of several cells. If you discharge the battery to zero, what will most likely happen is that one or more of the cells will "reverse" because they are weaker than the other cells. The reversed cell begins to accept a "backwards" charge from the other better charged cells around it. This will kill the battery. So we should stop the discharge at one point, rather than letting the pack slump down to zero volts. In the meantime, when the battery is at its full capacity, we should not plug the AC adapter to trickle charge the battery. It will overcharge the battery. 

Note: Over discharging and overcharging the battery will damage the battery.

What is batteries' memory effect?
A condition that occurs when a battery is charged to the same level several times consecutively (before being fully charged). The battery develops a chemical "memory" of that level and will not allow a charging past that point. You can avoid this through several complete discharge and recharge cycles.

How long will the battery last?
It is unscientific to generalize a battery's life because it is related to CPU power, screen brightness, and the specific situation under which you use it. If the capacity of the battery is the same as your original one, it can perform almost the same as your original battery.

I have the original battery nominal voltage is 14.4V or 14.8V, and the one you are selling only a nominal voltage 10.8V or 11.1V but
indicated the same models. How should I choose?
The safe working DC voltage for a laptop range of 5.5V to 24V. We all know that we are using lithium- ion batteries, and lithium-ion battery's characteristics are: the voltage increases when charging and decrease when discharging. For example: for a nominal 11.1V battery, it can provide a practical and effective operating voltage range: 9V-12.6V diverse from charging to discharging. According to DC power supply design principles, all manufacturers of laptop computers are designed so that the power supply circuit board, so whether you are using the original battery nominal voltage is 10.8,11.1 V, 14.4V, 14.8V or between them can all be used interchangeably, and are safe, you can rest assured that use.