Typical lithium cobalt carbon batteries were invented & commercialized by SONY in 1990 for the Walkman & Digital Cameras at production cost equivalent of $3700 per kWh at that time, having declined in the Tesla 4680 tab-less battery to $57 per kWh respectively in NMC chemistry.
Early Li-Ion were encased in a stainless steel housing & laser welded closed within an inert argon environment to prevent moisture from reacting with the lithium or cobalt used in the cathode while high purity graphite or hard carbon used in the anode material. Petrochemical electrolytes & an ion permeable membrane separator film between the anode & cathode enabled Li+ ions to shuttle between the anode & cathode during charge & discharge respectively. During the initial formatting charge a SEI layer formed that consumes some of the lithium while making the protective layer that prevent dendritic shorting from forming during later battery cycling & aging.
Li-PO or Lithium Polymer batteries replaced the heavy dense stainless steel case with aluminized mylar wrapped around the rectangular packet cells typically of hobby RC toys & in other portable electronics like laptops, tablets, smartphones & smartwatches respectively. This increased energy density to above 260wh/kg respectively, while the theoretical peak energy density of feasible lithium ion chemistries goes to 600wh/kg with 4th generation lithium sulfur batteries just now achieving commercialization in medium volumes for specialized aerospace drones where the highest energy density battery energy storage value exceeds the premium paid for lower volume production packs of high cost per unit, by contrast to mass manufactured common lithium cobalt chemistries found in high volume global production electronics like iPhone or Samsung Galaxy smartphones.
Cobalt the toxic conflict mineral mined by forced labor & children in fail states in Africa that many EV makers like Tesla sought to replace in newer chemistries that use more aluminum, nickel, manganese & even silicon in the anode instead of carbon for faster charging. At Toyota solid-state lithium ion batteries are being produced for pre-production beta testing EV's for the 2025-onward MY vehicle offerings of Toyota BEV' or battery electric vehicles, noting Toyota's early avoidance of EV's for the pursuit of hybrid electric vehicles based on NiMH or nickel metal hydride battery made in conjunction with Panasonic the battery supplier. These NiMH Prius batteries have better cold weather performance than typical Li-ion batteries below 40F or 10 C, in very cold winter weather like that encounter in parking lots of ski resorts as people go skiing or snowboarding all day, having driving their hybrid electric Toyota up the mountain pass to the ski resort with diesel & diesel electric chair-lift cable chair systems to move skiers & snowboarders up the mountain so they can carve the powder or groomed snow on the way back down in a silent symphony of kinetic ecstasy often with music in the ears under the head beanie to add some audio texture to the experiences of sheer joy :) I have been snowboarding since 1995 & absolutely love it!
Even living in Issaquah, my 19 Nissan LEAF cannot make it up the pass the Summit at Snoqualmie because climbing the pass at 70 MPH with the heat going full blast would juice the pack before I got there. I got the LEAF for local commuting to & from work. That's by far the closest ski-resort to our current address. Meg's 10 Prius III way better for longer energy intensive highway trips like that.
Back to the topic of EV's
Yes, replacing the battery packs in an older EV with a faded battery can cost between $5-20K, but there is also no engine or transmission. Consider the electric motors in most EV's super durable for 1 million miles of operation or 40+ years before the magnets lose a lot of their magnetic flux density from high heat levels respectively or heat cycling. There are examples of 2011 Nissan LEAF with over 300,000 miles ODO where the only major repair cost was a replacement 24kWh battery pack.
EV's like the Nissan LEAF have their best energy economy at lower speeds, achieving peak miles per kWh in the 8 mi/kWh at around 16 mph. As aerodynamic penalties start to add up at higher speeds the energy economy drops to 3.1 mi/kWh at common highway & freeway speeds of 55-80 mph. Sorry only American Imperial units in this one. I am writing about EV batteries for other English speaking people to consider, since people in America often have enough vehicle budget to buy a newer used Nissan LEAF or Tesla model something respectively.
The OG LEAF went through two major revision, resulting in a 30kWh variant in 2015 & stylistic upgrades & heat pump based more efficient HVAC systems being first commercialized in automotive formats in these later editions. In 2018 the 3rd generation was launched, called the 2nd Gen or ZE1, its actually a 3rd revision of the EM57+ motor drive system & 40kWh battery pack chemistry that's more fade resistant & with longer calendar life & cycle life vs the previous versions. A 62kWh & then 60kWh pack were made available on the SL+ variants. 2018-2023 model year Nissan LEAF are scheduled for a technical improvement upgrade to the battery & motor for the 2025 model year, probably with liquid cooling like that present on the Nissan ARIYA, which comes with up to 82 kWh of battery good for over 300 miles of range per charge for just over $60K new.
Most privately owned automobiles are parked 90% of the time for 21 hours per day. Many people get home before 8pm & do not leave for work until after 5am the next day. That's 9 hours parked, where even extension cord EVSE level 1 charging can add 2-5 miles of range per hour, depending on driving style. A lead foot driver in a Nissan LEAF going full blast on the highway driving like they stole it can achieve 2 mi/ kWh while a typical driver on the same route can easily get 3.5 mi/kWh, and with light hypermiling slower speeds & inertial conservation techniques its possible to get 5.1-7.1 mi/kWh especially in flatter topography environments with warmer but not hot weather.
If you are going to L3 44kW Fast DC charge a Nissan LEAF for 5-25 minutes on the go its best to do so very early in the morning around 5am when the outside temperatures are coldest and your LEAF at its lowest net temperature, or the battery temperature on the lower side of the scale as displayed in the Batter Temperature menu on the dash display computer where many other battery charging metrics & system functions can be adjusted via steering wheel controls.
More than 500,000 Nissan LEAF are on the worlds roads today, though the Model 3 from Tesla the best selling BEV after 2020 & still the best selling EV as of early middle 2023. I looked up the insurance cost for a Model 3, 2.5x than what it costs to insure our Nissan LEAF for the same model year, and the model 3 holds its value better so used ones are not available at steep discounts via depreciation like a used Nissan LEAF for example.
Na-ion, Solid State Batteries, Ceramic Batteries, Foam Batteries, Metal Air Batteries. There are literally more than 100 different alternatives to Lithium Ion batteries commonly used in electric vehicles. Even within the lithium ion space there are over a dozen different chemical options. Consider the LFP or lithium iron phosphate or lithium titanate or lithium sulfur batteries as examples. Lithium Cobalt Oxide cathode with Carbon Anode was just the first mass produced and oldest & most refined version that's also mass manufactured for all sorts of portable electronics today! The overwhelming majority of consumer electronics intended for mobile use cases rely on common lithium ion polymer batteries with a single cell nominal voltage of 3.7-3.85vdc and full charge voltage of 4.26vdc, though stopping charging at 4.11vdc makes these lithium ion batteries last 5x longer. They drain to around 3.0vdc & can be drained to lower voltages but doing so can damage the cell & cause a lasting loss of capacity instantly.
Existing lithium ion batteries do not work well if frozen cold & most EV's have batteries heaters to keep the pack temperature above 40 F in order to prevent freezing. If a lithium ion batteries is frozen & charged it causes lithium metal to plate out of solution & form a hard short circuit & catch fire, venting with flame & toxic smoke contaminate with burning cobalt & burning mylar coated in aluminum. I was charging out an iPhone battery that had been glued into the iPhone in south east Asia instead of being held in with polymer pull tabs the way Apple & Foxconn make em, and upon trying to pry this battery from the machine aluminum case of this older iPhone Plus, the LiPo cell ripped & got super hot & started smoking & then caught fire. This filled the 5000 sq. ft store with blue white smoke & the iPhone burned to a crips and looked like it had been in a hot bar-b-q oven for a while. I knocked the phone off the repair pad & bench into a sand bucket & took it outside & it continued burning & smoking intensely for a while, completely bricking or destroying the iPhone. Thankfully the man who owned it was expected this & had already backed up everything and was looking for an excuse to go buy a new iPhone & was not upset at all.
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