It seems like a month does not go by, without hearing news reports about battery explosions in e-cigs, headphones, smartphones or other electronic gadgets. Granted that stories about explosions are considered newsworthy, but has the statistical rate of battery failures actually gone up in the last few years? Has the impact of battery failures increased and if so, why? And, I am of course talking about Lithium ion batteries, the go-to battery chemistry in rechargeable electronic devices owing to their high energy density. I am certain you do not want to be carrying around a brick for a smartphone.
In recent years the practice of buying spare e-cigarette batteries online has started to increase, with some users scouting for higher amp-hour/power batteries in order to get a better vaping experience. This is particularly true for mechanical mod e-cigs, which are highly customizable and do not use protection circuitry. The battery protection circuit is what keeps a lithium-ion battery within its operating window, and prevents it from overheating, overcharge and other potentially dangerous situations.
My cousin recently came to me with a battery problem. He got a drone for Christmas, and he had not unboxed it for a while. Last Christmas, right? I asked. Apparently, it was the Christmas before (i.e a year and a half of being in a box). Uh-oh, I go. I almost knew what was coming. The drone obviously did not work, and I got to see a picture of a very bloated Lithium Ion pouch cell.
Your LiPo battery does need some attention from you every few months in the form of a periodic recharge, or you will end up with a cell that looks like this. My colleagues have brought me plenty of gadgets with the plastic case popped open from a bloated battery.
The first day of the Design for Reliability Conference in Baltimore, MD heralded the death of Physics of Failure (PoF). Craig Hillman, CEO of DfR Solutions made the announcement early in his welcome and introductions, explaining that as products get more complex, and reliability impacts on business become more serious, it is becoming ever more critical to have upper management participation. When the rest of engineering is busy pursuing “engineer for success”, PoF can ring negatively in the ears of management with its apparent focus on failure.
Not sure if you should attend the 2018 Design for Reliability Conference, March 19-21 in Baltimore? Well, here are 4 great reasons not to miss it this year!
“After a failure” investigations are typically performed to identify root cause of failure, calculate risk exposure and develop mitigation and remediation solutions. Just like with “before a failure” investigation, there are two specific test methods that could be applied to either of the two categories – non-destructive physical analysis (NPA) and destructive physical analysis (DPA).
Solder joint reliability is often a pain point in the design of an electronic system. A wide variety of factors affect solder joint reliability, and any one of them can drastically affect joint lifetime in a negative way. Properly identifying and mitigating potential causes of solder joint failure during the design and manufacturing process can prevent costly and difficult to solve problems later in a product lifecycle. Some of the most commonly observed solder joint failure contributors to consider are described here.
A common feeling among many designers and users of military electronic systems is nostalgia. Nostalgia for the good old days when the electronics industry was almost the exclusive supply chain of the military. While almost all aspects of integrated circuits (ICs) have improved over the past few decades (better, faster, cheaper), many in the military still long for the day when almost every semiconductor device on the market met or exceed their requirements without even asking.
Recently I, Greg Caswell, had full knee replacement surgery on my left knee to fix a problem with osteoarthritis. I found the overall experience interesting in that the approach the doctor’s used to assess the issue, develop a plan for improving the joints capabilities and finally performing surgery as the last possibility, was similar to the Physics of Failure approach DfR Solutions uses.
Performing a “before a failure” investigation on electronics is typically done for various reasons. One reason is to identify weak components or sub-systems before committing to a full-blown production run and its associated expenses. Comparison testing of similar component parts to reduce costs and increase reliability of existing designs, or against a competitor’s offerings is another reason. A “before a failure” investigation can validate a design to satisfy customer or market specifications, or regulatory obligations, which is common among the aerospace and medical devices fields.