Jan 25, 2012 Irvine, CA
The Micro Power Co. provided a great four-hour presentation on the latest Re-Chargeable Battery and Charging Technology. Battery technology evolves rather slowly. One of the big take aways was learning about the 4 key drivers in new battery technology and how it shapes the re-chargeable battery market. In order of market size:
1. Laptop computers drives the 100 Watt hour segment
2. Electric Vehicles drives the 50 Kilowatt hour segment
3. Grid Stabilization drives the 2 Megawatt hour segment
4. Electric Power Hand tools
Batteries are not what most people think they are, a simple cell much like an Alkaline that is also rechargeable. The Re-chargeable cells of today are contained in battery packs that contain sophisticated safety and power management electronics. These battery packs are a system that delivers more power, and more stable power output than was available just a few years ago.
The market is still dominated by the old Sealed Lead Acid battery, this however is about to change. Lithium Type Batteries are just shy of surpassing them. What Lithium Type batteries bring to the table is a more power for the same size package. For the same size a Lithium Type battery will have twice the power output as a Lead Acid Battery. Even compared to Nickel Metal Hydride batteries Lithium’s have a higher power output and a longer service life.
The most common type hence the better value are the cylindrical lithium battery. Being the most common offers economies of scale, and keeps the costs down. When designing a battery pack they suggested sticking with them most common types of battery a type 18650 or 26650. Custom batteries are available but come with a big price tag. Prismatic batteries, (rectangular or square) cost more but are a better fit where form fit is an important consideration such as portable consumer electronics.
Cell quality is critical low cost can mean cheap construction and early or even smoldering lithium cell failure. I was very impressed by the multiple levels of safety designed in to the whole battery system. Just for example several short video clips of Lithium Type battery failures where shown with some minor flame effects for all to enjoy. To cause this type of failure it took bypassing many levels of designed in safety. As noted Lithium Battery, failure is rare.
Inductive chargers are growing in popularity with Texas Instruments offering off the shelf circuitry. Texas Instruments offers a full suite of off the shelf electronic protection circuits for battery packs of many sizes. The use of LED or LCD gas gauges has become very popular, and they provide off the shelf solutions. Their technical support was outstanding.
Micro Power, Texas Instruments and Reliability Engineering all did a great job of making this technical presentation understandable to even a Product Manager like me.