A major problem with lithium ion battery pricing stems from the tremendously complex 3 week long formatting cycle at the manufacturing stage. 100% charging also damages lithium ion!
For over 7 years I have been working professionally with lithium ion batteries. I have several science degree's built on top of a life long fascination with energy technologies.
Save Your Lithium Ion Batteries from Early Death
30-80% Charge the key to long battery life in lithium ion powered devices. True for your cell phones, tablets, laptops and modern electric vehicles!
100% Charge Kills Lithium Ion : here is why;
Cathode Damaged by 100% Charge
Charging to 100% causes shrink swell damage to the Lithium Cobalt cathode by forcing lithium ions into the cathode with 4.26vdc of voltage pressure while oxidizing the cobalt transition metal from 3+ to 4+ state. The swelling associated with ion insertion above 3.8v causing damage to the cathode.
Anode Damaged by 100% Charge
When cells are fully charged to 100% (4.26v) this causes irreversible progressive chemical losses that reduce the cells cycle & calendar life. The carbon anode is damaged by lithium plating loses associated with deep cycling outside of the 30-80% range (~3.1-3.8 vdc ) Lithium lost by plating the carbon anode reduces the batteries performance, minimizing its ability to hold energy, reducing its cycle life and calendar life. New research in 2016 shows that lithium plating in the anode also causes anode cracking damage.
The Galaxy Note 7 was catching fire because of the separator film defects, namely they tried to smash the layers of the lithium ion sandwich too tightly with a thinner than normal separator film that was being penetrated by dendrite formations. New imaging techniques used to study lithium ion show these dendrites, and their ability to perforate a inapproprioately thin/ weak film. The cultural momentum to make the phone thinner and lighting while also giving better run time meant the engineers pushed the battery manufacturing method to an unsafe extreme. Sadly we need a new battery chemistry beyond Lithium Cobalt Carbon, something more dense like a super safe next gen Lithium Sulfur battery LiS to give lighter higher performance batteries in thinner packages.
LiCo:C
I am of course talking about Lithium Cobalt : Carbon batteries : the most common ones found in laptops, tablets, smartphones and electric vehicles today!
Alternatives
There are many variations of lithium ion that are much stronger & more relisilant than Lithium Cobalt Carbon, like lithium iron phosphated LiFePO4 or Lithium Titanate, but Lithium Cobalt Carbon offers one of the highest energy densities available. Volume production of Lithium Cobalt Carbon also dominate the LIB battery sector, thankfully not for long as Tesla brings the Gigafactory Online for its Panasonic co-developed NCA (Nickel Cobalt Aluminum) lithium ion 2170 batteries : the cells that will be inside PowerWall's and the Tesla Model 3' of 2018 and beyond!
Giga Factory
The scope of battery manufacturing at the Tesla Gigafactory by the billion is emblematic of the capital intensive huge factory I was talking about in the heading post! The Gigafactory will be one of the largest buildings in the world when it is complete. Tesla is focused on increasing operational density in the facility to maximize the reduction of costs, thereby enabling increasingly feasible energy storage solutions for homes and electric vehicles. Elon Musk noted that this has to be done on a big scale because we live in a big world with a lot of people, and to make a big difference you have to go to the Billion scale, because that's on the scale of human population, namely around 7 billion!
New Research provides LIB manufacturers a faster method for cell wetting and initial formatting, bringing production times from 3 weeks down to 4 days. This means smaller less expensive factories will be able to produce cheaper batteries.
http://www.greencarcongress.com/2017/02/20170203-ornl1.html
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