Unfortunately, no laptop battery lasts forever, and the day will eventually come when yours no longer works as well as it once did. You might see this as being a good excuse to buy a new laptop, but not everyone has that kind of money at their disposal. Replacing the battery may be an inexpensive alternative, and it’s probably a lot easier than you think.
But how can you tell if your battery needs to be replaced? And how can you find out your laptop battery type?
What Do the Different Types of Laptop Batteries Have in Common?
There have been three primary types of laptop batteries1 over the years, and if you’ve been using laptops for a while you’ve probably encountered all of them. Each of them works a little differently, using different chemical processes, and they each have their pros and cons.
However, they share a few common factors that are worth bearing in mind, especially if you’re looking to prolong your battery’s life:
- They all have a finite number of charge cycles. A charge cycle is defined as charging the battery to full capacity and then fully discharging it again.
- Batteries discharge power when idle. Some will discharge quicker than others, but if you fully charge your battery and then don’t use your laptop for months, it’ll have less than 100% remaining.
- Warmer temperatures cause laptop batteries to discharge faster. It’s a good idea to always keep your laptop cool, but if you store your laptop, make sure it’s not somewhere warm.
- Don’t make it a habit to always drain the battery down to 0% – something that can happen easily if you’re using a gaming laptop for lengthy gaming sessions. While it’s a good idea to drain the battery completely from time to time, allowing it to frequently drain completely can cause permanent damage to the battery.
What Are The Three Different Types of Laptop Batteries?
The oldest type of laptop battery is Nickel Cadmium (NiCad) – and you could say it’s responsible for giving all rechargeable batteries a bad name.2 This is the battery that’s infamously known for the “memory effect,” the name given to the situation where the battery shows as being fully charged but then lasts only a few minutes.3
If the battery wasn’t completely drained at the start of the recharging process, crystals could form inside that would eventually prevent the battery from becoming fully charged again. In essence, the battery would incorrectly think it was fully charged, when in fact it wasn’t.
That said, if it was properly maintained, a NiCad battery could have a lifetime of 1500 charge cycles, making it the battery with the longest potential lifespan on the list. To do this, it’s best to let the battery discharge as much as possible (although not necessarily to zero) before recharging it again.4
If your laptop is relatively new, it’s unlikely to have a NiCad battery installed as manufacturers tend to use Lithium-Ion (Li-ion) batteries now. However, if you have an older laptop that requires a NiCad battery, it’s still possible to buy replacements if you need them.
Manufacturers started to use Nickel Metal Hydride (NiMH) batteries as an alternative to the NiCad batteries, but whereas NiMH batteries don’t suffer from the memory effect, they don’t last as long either. In fact, a properly maintained NiMH battery may only be good for 500 charge cycles – that’s just a third of the older NiCad batteries.5
The best way to maintain your NiMH battery? It’ll last longer if you charge it when it’s partially depleted, but you should allow it to completely drain after every four or five charges before recharging it again.
The last type of laptop battery is also the most common and is now found in many of the rechargeable electronic devices we use on a daily basis. Lithium-ion (Li-ion) batteries are something of a middle ground between NiMH and NiCad batteries in that they’re good for up to 1000 charge cycles but they don’t suffer from the memory effect.
Like the NiMH batteries, you can potentially increase the number of charge cycles by partially discharging the battery and then recharging it again. They’re also more environmentally friendly and have a rapid charge option. This means you can potentially get the battery charged to about 80% in an hour or so.
The downside? They lose their capacity to be fully charged over time and may have a realistic lifespan of only two years.
How to Test Your Laptop Battery’s Health
If you’re using a Windows laptop, you can check your battery’s health by using Windows’ PowerShell terminal. Here’s how:
- Click the Search icon in the bottom left corner of your screen.
- Type PowerShell and then click on the first result that appears. A window will appear with a command line prompt.
- Type powercfg /batteryreport and then press Enter. (Be sure to leave a gap between the powercfg command and /batteryreport.)
- Windows will save the report to your hard drive; it will give you the location as C:\Users\Username, where Username will be the username you use to log in to your laptop.
- Look for an HTML file called battery-report.html and double-click to open it.
There’s a lot of useful information here, but there are a couple of sections you’ll be most interested in.
- Installed batteries – ignore the battery name and manufacturer as it won’t help you find a replacement. However, the following information could be useful:
- Design capacity and Full charge capacity – This tells you how much charge the battery was designed for and how much a full charge will currently give you. To find out your battery’s health, divide the full charge capacity by the design capacity and then multiply by 100 to get a % figure. For example, if a laptop’s design capacity is 37,350 mWh and its current full charge capacity is 35,340 mWh, then its health is 94.6% and doesn’t need to be replaced.
- Cycle count – this shows you how many power cycles the battery has already gone through and can give you a good idea of how many cycles it has left.
- Battery life estimates – you’ll find this at the bottom of the report, and while the estimates can vary considerably, it should give you a rough idea of how long you can expect the battery to last on a full charge.
How to Find a Replacement Laptop Battery
If, after checking your battery’s health, you determine you need to replace the battery, then you can follow these easy steps to find out which battery you need.
- If you don’t already know it, find out your laptop’s make and model. This can sometimes be found on a sticker close to the mousepad or keyboard. If not, have a look at the underside of the laptop; there should be a label there with the information you need.
- If your label is missing, Windows can also tell you the make and model.
- Click the Search icon in the bottom left corner of the screen.
- Type settings and then click on the gear icon at the top.
- Click on System in the top left corner.
- Click on About at the bottom of the list in the left pane.
- The model number will appear under Device Specifications.
- Use your laptop’s make and model to search for the battery online. The chances are you’ll be able to easily find a compatible battery through an online retailer such as Amazon. Alternatively, contact your laptop manufacturer to order an original part. Be aware that this might cost you more as genuine manufacturer parts are more expensive.
- If your label is missing, you’ll need to check the battery itself to find its part number. Older laptops have an external battery that can be slotted into the underside of the laptop. In this scenario, there’ll be a latch (or sometimes two latches) to release the battery. Release the latch so that the battery can be removed and then look for a series of letters and numbers in large print. This is the battery’s model number.
- You may not be able to replace the battery on newer and smaller laptops, as they’re completely internal and cannot be easily removed. In this situation, there’ll be no latches on the laptop’s underside, and the only way to remove the battery is to unscrew and then remove the bottom. Unlike desktop PCs, laptops aren’t designed to be upgraded by the customer as their components are in a small, compact area. If you have a laptop with an internal battery, your best course of action is to take it to a service center and have a professional do the work for you.
Whether you’re able to replace the battery yourself or need a professional to do it for you, there’s no reason to throw out your laptop simply because the battery can no longer keep a full charge. Replacing the battery can be an inexpensive solution that won’t hurt your wallet and can save you the hassle of re-installing software and moving all your important files. And, as an added bonus, it could prolong your laptop’s life by another couple of years.
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- Anon. The Different Types of Laptop Batteries. Dell.com. Accessed October 7, 2021.
- BatteryStuff.com. What The Heck is a NiCd Battery? Batterystuff.com. Published November 5, 2019. Accessed October 15, 2021.
- Electronics Notes. NiCd Nickel Cadmium Battery Memory Effect. Electronics-notes.com. Accessed October 15, 2021.
- Jackman M. Understanding and maintaining laptop batteries. Techrepublic.com. Published October 25, 2000. Accessed October 15, 2021.
- Custom Power. Nickel Metal Hydride. Accessed October 15, 2021.