Things you thought you knew about batteries

They are the most readily available source of power for our army of portable devices. They provide us with precious energy, right down to the last milliamp. They are invariably unavailable in your local garage on Christmas Day. I am, of course, talking about batteries. But what do we really know about the professional application of this most ubiquitous of products? Here we bust some myths and shed some light on the most commonly held misconceptions about batteries in professional applications.

1. I need to fully charge my new device before first usage - FALSE

First you spend countless hours in the shops hunting down the perfect device, it may be a new laptop, phone or camera. You rush home, rip away the packaging like an excited child on Christmas morning and turn on your device, only to find instructions telling you to 'ensure the battery is fully charged before first use'.

The same is true in many professional applications, with even experienced end users still believing they need to charge the device fully before first use.

Whilst this was true once, the advent of modern Lithium-ion (Li-ion) battery technology means that devices can be used straight away without harming the battery.

So why do many manufacturers still print the warning? It seems this is a marketing and reputation management tactic more than anything else; to ensure that customers have the most engaging first interaction. That wouldn't be the case if your battery died within five minutes of use!

However, the nature of Li-ion batteries means that certain precautions do have to be taken during the shipping process. Li-ion batteries must retain a minimum charge to prevent them becoming unstable. When not in use, the onboard microcontroller, which itself consumes around 5% of charge per year, ensures that the battery is turned off before complete discharge.

Conversely, shipping a fully charged battery can also be dangerous as such a high volume of energy is not safe during transit or good for battery cells. This is why most original equipment manufacturers (OEMs) charge batteries to around 50% for transit.

Here at Accutronics, we use a special sleep-mode for shipping. This ensures that the battery exhibits negligible power consumption during shipping, recovering full functionality when first powered on. If you want to know more about it, get in touch.

Accutronics' credit card battery provides vital power to portable medical devices

2. I must discharge my battery fully, before recharging each time - FALSE

This myth was a reality in the 70s and 80s when Nickel Cadmium (NiCd) and Nickel-Metal Hydride (NiMH) batteries were commonly used. The active materials used in these batteries meant that, when put on charge, a cell's capacity was limited to the previous discharge level. This problem was overcome by fully discharging the battery each time.

The memory effect has been all but eradicated with the use of modern Li-ion batteries, which should only be discharged to around 20% before being recharged.

This doesn't mean that batteries don't degrade over time. A typical Li-ion battery has around 300-500 optimum cycles before it starts to lose capacity. However it is not necessary to start each cycle after a full charge and discharge. A cycle can equally go between half full and half empty; how's that for philosophical battery debate!

So, it turns out that some of the things you thought you knew about batteries were false and some of those myths actually create more questions than they provide answers. If you want to really get to the bottom of how to charge, transport and manage batteries in professional and medical applications, get in touch. We have a whole team of myth busters ready to help.