Samsung Unveils New Electric Car Batteries For Up To 430 Miles of Range (electrek.co)

An anonymous reader quotes a report from Electrek: At the Frankfurt Motor Show (IAA Cars 2017) this week, Samsung's battery division, Samsung SDI, showcases a new "Multifunctional battery pack" solution to enable more range in electric vehicles as the Korean company tries to carve itself a bigger share of the growing automotive battery market. Most established automakers, like Nissan with the LEAF or even GM with the more recent Chevy Bolt EV, have been using large prismatic cells to build their electric vehicle battery packs. Tesla pioneered a different approach using thousands of individual smaller cylindrical li-ion battery cells in each pack. Earlier this year, Samsung unveiled its own '2170' battery cell to compete with Tesla/Panasonic. Now they are claiming that they can reach an impressive energy density by using those cells in new modules: "'Multifunctional battery pack' of Samsung SDI attracted the most attention. Its users can change the number of modules as they want as if they place books on a shelf. For example, if 20 modules are installed in a premium car, it can go 600 to 700 kilometers. If 10 to 12 modules are mounted on a regular sedan, it can run up to 300 kilometers. This pack is expected to catch the eyes of automakers, because they can design a car whose mileage may vary depending on how many modules of a single pack are installed."

Comments

The figure that matters...

[Rei]

.... is not Wh/kg. It's $/kWh. That is by far the number one aspect for increasing adoption. Tesla for example gets a constant stream of companies pushing new battery technologies, wanting to talk about every aspect except for that one: cost per unit energy. They're always asked to cut straight to the chase.

Of course, we're not even given Wh/kg here in this article.

After cost per kilowatt hour, the number two factor is longevity. Because it correlates directly with cost. Generally it means you have to have shallow cycles (low DoD) if the battery isn't durable, meaning more batteries. In particular, longevity in varying temperature and charging condtions is important. In short, longevity works out to just another aspect of cost.

Barring some unusual problems, cell safety is usually #3 or #4. Not higher, because failures can, and already are, controlled. See for example fire tests of Tesla powerwalls. A combination of physical isolation, active quench (circulating coolant), passive quench (coolant / structure thermal mass, expansion space, venting), and a wide range of other mechanisms mean that you really have to pull out all the stops to burn the packs; there have been Teslas which burned to the ground, down to smouldering wrecks, still without managing to ignite the pack.

(Honestly, it amazes me that it's considered acceptable to store massive amounts of gasoline just in one big open tank - no isolation / compartmentalization / quench systems. Just dump it in and there you go! Not surprising that there's ~200k car fires in the US alone every year)

The other big competitor with safety is power density - the mix of ion mobility (how fast it's physically possible to charge / discharge the cell) and efficiency (how much heat you have to remove from the cells to do so). The heat removal rate is also affected by the heat tolerance. Charge speeds are a more significant limiting factor to the number of purchases than range, and the power output of the packs and high torque they allow are one of the big selling points of EVs.

Heck, Wh/kg (gravimetric energy density) isn't even the most important energy density measure. Practical EVs are not limited by their weights - heck, the Model 3 SR slots right into the middle of its class (compact midrange sedans in their various configurations, and the LR, while on the heavier side, still has some heavier ICE competitors). Their ranges are limited by how many cells you can physically fit into the pack without making the skateboard unreasonably bulky. For example, the Model 3 skateboard, at current cell volumetric energy densities, simply can't scale to higher than 75kWh. Doesn't matter what the gravimetric energy density is - if you want more, you need to improve the volumetric energy density.