How I charge my cell phone battery?
Smartphones manage appointments, connect us with customers and business partners, allow us to check up on work, message, email, stay informed on the daily news, find the nearest coffee shop or get the answer to whatever random burning question we might have “OK Google, what percentage of Microsoft is owned by Bill Gates” (BTW its 4%).
The average person checks their Smartphone 9 times an hour. No wonder one of the biggest fears of our time is that we might suddenly loose access to the digital world because we run out of battery power.
Smartphones have a replacement cycle of about 2 years and that seems to be what the battery life of the phone was designed to. My last phone had more than enough battery power to get through my day when it was new, but capacity started deteriorating as it reached the 2 year mark, requiring me to recharge in the afternoon in order to get through the day.
Having said that, my charging habit was what most smartphone users do. I would plug it in to charge overnight in order to have a 100% charged phone in the morning when I get up. In consequence my battery went through the most “stressful part of the charge cycle (from 85% to full 100%) every night 365 times a year. So each night the full charge cycle chipped away at the battery’s State of Health (SOH) and at its capacity.
The simple explanation for this is that in a 4.2V Li-ion battery the charge voltage remains 4.1Volt and below until the battery reaches a State of Charge (SOC) of around 85-90%. Only then does the voltage rise to the maximum of 4.2V in order to fill the last 10-15% of the battery. Studies at Cadex have shown that if we can keep the voltage at 4.1V (keep the SOC under 90%) we can more than double the life of the battery.
How I charge my phone now:
When I replaced my phone I decided to change my charging habits. Instead of charging the phone overnight, I plug it in when I get home from work and unplug it again after dinner. Depending on my use during the day the SOC will be between 70% and 90% by the time I go to bed.
In the morning I have 2 more opportunities to top off charge in order to reach the optimal 80-90% I want to have for my work day. I can plug it in during breakfast and/or during my drive to work.
In the beginning this took some getting used to but by now it is part of my regular routine and so far the battery capacity of my 1 year old phone seems to be performing the same as when it was new.
Markus Pauli, COO Cadex Electronics Inc.