A laptop battery is a rechargeable lithium-ion battery that powers your laptop when it's unplugged. On a single charge, most laptops run about 6 to 15 hours depending on the model and what you're doing. Over time, every lithium battery slowly loses capacity, and most laptop batteries keep enough health for about 2 to 4 years, or roughly 300 to 1,000 full charge cycles.
In this laptop battery guide, we explain how lithium batteries work, what affects battery life, how to check battery health, how to make your battery last longer, and how to replace and recycle a laptop battery safely. For more laptop terms, visit our laptop glossary.
How Lithium Laptop Batteries Work
Laptops use lithium-ion batteries because they store a lot of energy in a small, light package and can be recharged hundreds of times. Inside the battery, lithium ions move from one side of each cell to the other when the battery charges, then move back to power the laptop. A small circuit board in the battery pack manages charging, temperature, and safety.
Lithium-ion vs. lithium-polymer laptop batteries
Battery type | What it is | Where you'll find it |
Lithium-ion (Li-ion) | Cylindrical or prismatic cells with liquid electrolyte, grouped into a pack | Older laptops and some larger or budget models |
Lithium-polymer (Li-po) | Flat, flexible pouch cells that can be shaped to fit thin designs | Most current thin-and-light, 2-in-1, and premium laptops |
Both types are lithium-ion chemistry and follow the same care, travel, and recycling rules. Lithium-polymer cells are popular in modern laptops because their flat shape fits slim designs.
Laptop battery capacity: Wh, mAh, and cells
Watt-hours (Wh): The total energy a battery stores; a higher Wh rating usually means longer battery life on the same laptop
Milliamp-hours (mAh): Charge capacity at the battery's voltage; less useful for comparing laptops because voltages differ
Cells: The individual battery units inside the pack, such as a 3-cell or 4-cell battery
Most laptop batteries are rated between about 40Wh and 100Wh. Thin laptops often use 40Wh to 70Wh batteries, while gaming laptops and mobile workstations often use 70Wh to 99Wh batteries. You'll find the Wh rating on the product spec sheet or printed on the battery. Batteries over 100Wh have extra limits for air travel, as our laptop weight and carry-on guide explains.
What is a battery charge cycle?
A charge cycle is one full use of a battery's capacity, from 100% down to 0%, whether that happens all at once or across several partial discharges. For example, using 50% of the battery on two different days counts as one cycle. Battery wear is tracked by cycles, so shallow, partial charges are gentler on a lithium battery than repeated full drains.
Laptop Battery Life
Laptop battery life means two different things: how long a laptop runs on one charge, and how many years the battery lasts before it needs replacing. Most laptops run about 6 to 15 hours per charge with everyday use, and most laptop batteries last about 2 to 4 years before their capacity drops noticeably.
How long does a laptop battery last on one charge?
Laptop type | Typical battery life per charge | Why |
Thin-and-light and AI laptops | 10 to 20+ hours | Efficient processors, integrated graphics, and power-saving NPUs |
Standard everyday laptops | 6 to 10 hours | Balanced specs and mid-size batteries |
2-in-1 laptops | 8 to 14 hours | Efficient chips; touch screens use some extra power |
Chromebooks | 8 to 12 hours | Lightweight operating system |
Gaming laptops | 3 to 6 hours | Dedicated GPU and high refresh rate display draw more power |
Mobile workstations | 4 to 10 hours | Pro-grade GPUs and high-performance processors |
These are typical real-world ranges. Battery life listed on a spec sheet is measured under specific test conditions, such as video playback at a set brightness, so your results will vary with how you use the laptop. To compare models, see our guide to HP laptops with the longest battery life.
What drains a laptop battery fastest?
Screen brightness: The display is often the single biggest power draw
Demanding apps: Gaming, video editing, and 3D work push the processor and GPU
High refresh rate displays: 120Hz and higher screens use more power than 60Hz screens
Background apps: Sync tools, updates, and browser tabs keep running when you're not looking
Wireless connections: Wi-Fi, Bluetooth®, and cellular radios searching for signals
Keyboard backlighting and external devices: Backlights and USB accessories draw power from the battery
How long does a laptop battery last overall?
Most laptop batteries last about 2 to 4 years, or 300 to 1,000 charge cycles, before they hold noticeably less charge. Heat, frequent full drains, and keeping a battery at 100% for long periods speed up wear. A battery that holds less than about 80% of its original capacity is usually considered worn. Learn more about how long laptops last overall in our article on average computer lifespan.
Laptop Battery Health
Battery health is how much charge your battery can hold now compared with when it was new. A new battery is at or near 100% health. As the battery ages, its maximum capacity shrinks, so a full charge lasts less time. Most batteries are considered worn when health falls below about 80%.
How to check laptop battery health in Windows
Open Command Prompt. Select Start, type cmd, and open Command Prompt.
Create a battery report. Type powercfg /batteryreport and press Enter.
Open the report. Windows saves an HTML file, usually in your user folder, and shows the file path.
Compare capacities. Find Design Capacity and Full Charge Capacity under Installed batteries.
Calculate battery health. Divide Full Charge Capacity by Design Capacity and multiply by 100. For example, 45,000 mWh divided by 50,000 mWh is 90% battery health.
The battery report also lists the cycle count and a history of recent battery use. Many HP laptops include a battery check in HP Support Assistant or the HP PC Hardware Diagnostics tool, which can also test whether the battery needs replacing.
Signs of a failing laptop battery
Short run time: A full charge lasts much less than it used to
Sudden shutdowns: The laptop turns off at 20% or 30% instead of running down slowly
Charging problems: The battery won't charge past a certain level or isn't detected
Windows warnings: A notification suggests replacing the battery
Heat: The battery area feels unusually hot during light use or charging
Swelling: The case bulges, the trackpad lifts, or the keyboard deck looks uneven
A swollen battery is a safety risk. If you see swelling, stop using and charging the laptop right away and follow the steps in the replacement section below. Our backups, troubleshooting, and resets glossary covers other warning signs that a laptop needs repair.
How to Extend Laptop Battery Life
To make a laptop battery last longer, lower the screen brightness, turn on battery saver, close apps you aren't using, and keep the laptop cool. To help the battery stay healthy for more years, avoid keeping it at 100% all the time, avoid draining it to 0%, and use built-in charge-limit settings if your laptop has them.
Settings that make each charge last longer
Turn on Energy Saver or battery saver: In Windows 11, go to Settings > System > Power & battery
Lower screen brightness: Even a small drop in brightness can add noticeable run time
Choose a power-saving power mode: Set the power mode to Best power efficiency when you're unplugged
Lower the refresh rate: Switch a 120Hz or higher display to 60Hz for everyday work
Close background apps and tabs: Check Task Manager for apps using a lot of power
Turn off keyboard backlighting: Our guide on turning keyboard lighting on and off shows how
Keep the laptop updated: Windows, driver, and BIOS updates often include power improvements; see our laptop updates glossary
Charging habits that protect battery health
Habit | Why it helps |
Keep the charge between about 20% and 80% when you can | Lithium batteries wear faster at very high and very low charge levels |
Avoid heat | High temperatures speed up battery aging; don't charge on a bed, pillow, or in a hot car |
Use the right charger | An HP-approved charger with the correct wattage charges safely and efficiently |
Store at about 50% | For a laptop you won't use for weeks, charge it to about half and power it off completely |
Don't worry about occasional full charges | Charging to 100% before a long trip is fine; it's staying at 100% for long periods that adds wear |
HP battery care features
Many HP laptops include built-in tools that manage charging for you:
HP Battery Health Manager: A BIOS setting on many HP business laptops. The Maximize my battery health option limits charging to about 80% for laptops that stay plugged in most of the time. Learn more on the HP Battery Health Manager support page.
Adaptive Battery Optimizer: A BIOS setting on many HP consumer laptops that adjusts charging over time to reduce battery wear
Smart charging in the HP app: On supported models, HP Support Assistant or the HP app can turn on smart charging to reduce time spent at full charge
Available features and names vary by model, so check your laptop's BIOS or HP app settings. For lighter, faster chargers, see our chargers and power glossary or shop the HP 65W GaN USB-C laptop charger.
Laptop Battery Replacement and Disposal
Replace a laptop battery when it no longer lasts long enough for your day, health drops below about 80%, or it shows signs of damage like swelling. Never throw a laptop battery in the trash or curbside recycling bin. Lithium batteries can start fires, so take them to a battery collection site, an electronics recycler, or a household hazardous waste facility.
How to replace a laptop battery
Find your battery part number. Check the battery label, your laptop's product specifications, or HP Support Assistant.
Choose a genuine replacement. A genuine HP battery made for your exact model fits correctly and works with the laptop's charging and safety systems.
Decide who installs it. Most current laptops have an internal battery that should be replaced by a trained technician. Some models allow user replacement following the service manual.
Back up your files. Save your data before any repair.
Recycle the old battery. Take the old battery to a proper collection point.
HP offers battery replacement options for many models. To learn which other laptop parts you can replace, see our laptop installations and upgrades glossary.
What to do with a swollen laptop battery
A swollen laptop battery is a damaged lithium battery and a fire risk. If your laptop case bulges or the trackpad or keyboard lifts:
Stop using the laptop and unplug the charger
Shut the laptop down if you can do so safely
Don't press, puncture, or try to remove the battery yourself
Move the laptop to a cool, nonflammable surface away from anything that can burn
Contact HP support or an authorized service provider for replacement
How to dispose of a laptop battery safely
The US Environmental Protection Agency (EPA) says lithium-ion batteries and devices that contain them should not go in household trash or recycling bins. Instead:
Cover the battery terminals with nonmetallic tape or place the battery in its own plastic bag
Take the battery to a battery collection site, often located at electronics retailers
Use a certified electronics recycler or your local household hazardous waste program
Recycle the whole laptop through an electronics take-back program if the battery is built in
If you're recycling the entire laptop, erase your data first. Our laptop security and safety glossary explains secure disposal, and our recycling glossary covers HP recycling programs.
Laptop Battery FAQs
How long should a laptop battery last?
A laptop battery should last about 6 to 15 hours on a single charge with everyday use, depending on the model and workload. Over its lifetime, a laptop battery typically lasts about 2 to 4 years, or 300 to 1,000 charge cycles, before its capacity drops noticeably.
Is it bad to leave a laptop plugged in all the time?
Leaving a laptop plugged in all the time won't damage it, because the laptop stops charging when the battery is full. Keeping a lithium battery at 100% for long periods can speed up long-term wear, so turning on a charge-limit setting such as HP Battery Health Manager helps if the laptop stays plugged in.
Should I let my laptop battery drain to 0%?
No, regularly draining a lithium laptop battery to 0% is not recommended. Lithium-ion batteries last longer when kept between about 20% and 80% charge, and frequent deep discharges add wear.
How do I check my laptop battery health?
On a Windows laptop, open Command Prompt, type powercfg /batteryreport, and open the report it creates. Divide the Full Charge Capacity by the Design Capacity and multiply by 100 to find battery health as a percentage.
What is a good battery health percentage for a laptop?
A laptop battery health of 80% or higher is generally considered good. Below about 80%, the battery holds noticeably less charge, and replacing it may be worth considering.
Can I replace my laptop battery myself?
Some laptops allow user battery replacement, but most current laptops have internal batteries that should be replaced by a trained technician. Using a genuine battery made for the exact laptop model is the safest choice.
What should I do if my laptop battery is swollen?
If a laptop battery is swollen, stop using and charging the laptop, place it on a cool, nonflammable surface, and contact the manufacturer or an authorized service provider. Never press, puncture, or try to remove a swollen battery yourself.
How do I dispose of an old laptop battery?
Take an old laptop battery to a battery collection site, certified electronics recycler, or household hazardous waste facility. Do not put lithium-ion batteries in household trash or curbside recycling, and tape the terminals before dropping the battery off.
Why is my laptop battery draining so fast?
A laptop battery drains fast when the screen is very bright, demanding apps or background processes are running, or the battery has aged. Turning on battery saver, lowering brightness, and closing unused apps help, and a battery report can show whether the battery itself has worn out.
What does Wh mean on a laptop battery?
Wh stands for watt-hours, a measure of how much energy a battery stores. A higher Wh rating usually means longer battery life on the same laptop, and most laptop batteries are rated between about 40Wh and 100Wh.
