The Journal of catalysis and rutinology (ChemCatChem) has a Global Impact Factor of 6.836 for 2018. You would need to read through up to about 147 articles per month to maintain this review-based journal. This means that a scientific researcher or graduate student will invest an average of 149 hours – nearly 10 days – per year to cover the monthly selection of articles. On average, students spend 8% of their study time on print reading every day.
What is the Cycle Life of a Battery?
There is no specific formula to calculate the life of a battery. Commonly, a battery has a current rating of 1-1.5 Amps. Battery cycle life is typically reported with the alkaline number or 3rd grade AA NiCd or NiMH cells at 1000 charge/discharge cycles at zero amps.
The cycle life of a battery is the number of times it can be charged and discharged before its maximum capacity declines. Different lithium-ion batteries have different capacities, which means they also have different cycle life measurements. This is a regular part of notebook laptop batteries, but portable batteries tend to last 20-30% less.
It can be hard to know when you need a new battery for your laptop. One way to determine the cycle life is to measure the mAh number on the battery label. This tells you the capacity of the battery in milliamp hours. A higher mAh number means more cycles, so for laptop batteries 4600mAh will last longer than 2756mAh.
How to Determine Cycle Life
Knowing your cycle life is very important when getting the most out of your battery charge. There are many measurements, but four key indicators can be used to determine cycle life: cycles per hour (cph), time-to-cycle efficiency, state-of-charge voltage, and capacity. Cycle Life is determined by calculating Kt/Ah divided by Cph.
Cycle life is a measure of how many times a battery can be charged and discharged and still perform as expected. It is typically expressed in terms of the number of cycles that the milliamp-hour capacity delivers. FIGURE 3 (below) illustrates cycle life ranges for batteries in a plug-in hybrid electric vehicle. This graph clearly demonstrates the advantages of lithium ion batteries over nickel-cadmium batteries in automotive technology, as well as the importance of cycle life in battery selection.
The cycle life of the battery that comes with new Apple MacBook Pro laptops is defined by how many times it can take a full charge and discharge without losing power at a specified power draw.
The battery specifications are in MB Bar of 11.6 grams and the cycle life is 800 charge cycles.
The best way to figure how many cycles a battery has is by looking at the “cycle count.” This number tells you how many times it will take for completely charge and discharge one time. 10,000 hours would be an example of 100 cycles
One of the first things to track when considering a potential upgrade is battery life. It’s convenient that certain models of laptops have very specific battery specifications built in to their name. For example, the “MacBook Pro 13-inch with Retina display” has a cycle count limit of 1,000, whereas the Chromebook Pixel only allows a cycle count of 822.
How to Replace Your MacBook Pro Battery
Before you begin your battery replacement, it’s necessary that you firstly determine how many cycles your battery has already gone through. To do so, observe the progress indicator for your laptop on the MacBook and Apple battery icon in the menu bar Right click on the menu bar icon, select System Information and look for Battery cycle count in Battery Cycle Count at the bottom of the window.
MacBook batteries come in different cycles to help ensure they fit with MacBook Pro operating systems. The four most common are:
If you could reduce the number of times your MacBook air gets stopped and turned off, think about saving a boatload of money for your electricity bill! A study done by Power Compare Services, a UK-based power comparison and price comparison engine at www.powercompare.co.uk, that looked at global electricity prices found that MacBook users are spending an average $45.68 a year on their power bills compared to the current average annual cost of $34 in countries like Ireland, France, Canada and Italy. That amounts to nearly $12 less per year when the laptop is running on this blog title’s recommended cycle rate!
Compared to a normal laptop battery, which is designed to last for only eight hours, the lithium ion battery in a MacBook Pro can last up to 400 cycles.
There’s a lot going on to make the battery last a really, really long time. As you can see, the more heat your laptop generates while in use, the shorter-lived its battery will be. What’s worse, many common parts of laptops give off high levels of heat themselves, so remember to keep it cool and stay away from extensive custom graphics cards, fast processors and other components that quickly produce heat.
As always, these are just my personal thoughts on this. Depending on what your needs are, you could use a one-wire sensor, or a multi-wire sensor that uses either for the battery status or current sensor. I personally prefer using a single wire sensor so that’s what I used in this project.