I have a Dell Precision 5520 that originally came with a 130W, 19.5V charger and a 97Wh battery. After a charging problem, I took it to a repair shop while I was away. They replaced the battery, but the replacement reports a design capacity of only about 63Wh instead of 97Wh. They also returned the laptop with a 65W charger.
When I start the laptop, the BIOS identifies the 65W adapter and recommends a 130W adapter. The battery also loses charge while the laptop is plugged in. The technician claims that using the original 130W charger caused the battery circuit to overheat and burn, and says I should not use the computer while it is charging.
Is that explanation technically valid? Could I safely buy a new 130W Dell-compatible charger, or could it damage the laptop or the lower-capacity replacement battery?
4 Answers
The charging circuit itself may have a known hardware fault, especially since the port was reportedly melted. A new 130W adapter is appropriate, but it will not fix a damaged port, DC-in board, motherboard charging circuitry, or an incorrectly installed battery. I would have the machine inspected by a reputable Dell-qualified repair technician and ask the original shop for an itemized explanation or refund for the incorrect parts.
The technician's explanation is misleading. A 130W adapter does not force 130W into the laptop; the laptop draws only the power it needs. A properly functioning 130W charger is the rated supply for this model and should be used. A faulty charger, damaged charging port, or defective charging circuit could cause overheating, but simply being rated at 130W would not.
The original charger had already stopped working, and the technician said the charging port was melted. Could that defective charger or port have caused the damage instead?
Battery capacity and charger wattage are separate issues. The charger rating is based on the laptop's total power requirements plus enough extra capacity to charge the battery. A 63Wh battery does not make a 65W charger the correct adapter, and the shop should have explained or approved the smaller replacement battery before installing it. The replacement battery may also be the wrong part or a lower-capacity compatible model.
The 65W adapter is underpowered for a Precision 5520. It may run the laptop, but under load the system can consume more than the adapter provides, so it uses the battery to make up the difference. That explains the battery draining while plugged in and the BIOS warning. Get a good-quality 130W Dell-compatible adapter with the correct voltage and identification circuitry.
A higher-rated adapter such as 180W generally would not damage the laptop either, provided it has the correct voltage and is properly recognized. The important thing is using a compatible, functioning adapter rather than an unverified generic one.