- 1 Information
- 2 Battery Capacity Loss
- 3 Li-Ion Technology
- 4 Cost
- 5 Range/Power Consumption
- 6 Battery Capacity Behavior
- 7 Battery Bugs/Problems
- 8 Emergencies
- 9 12V Battery
- 10 Medium to Long-Term Storage
- 11 Aftermarket
The battery consists of laminated lithium-ion cells with lithium manganate cathodes . The battery modules are currently manufactured at the Automotive Energy Supply Corporation (AESC) operation in Zama, Japan, which is a joint-venture of Nissan Motor Co., Ltd. and NEC Corporation. The battery contains around 9 lbs of lithium .
The Leaf has a range of 100 miles, based on the LA4 EPA Urban Dynamometer Driving Schedule (UDDS). Owner can pre-heat or pre-cool car prior to unplugging from charger in order to maximize range . There is more info on driving range on the Leaf Information Center Wiki.
A "SOC Check Sheet", showing VIN & number of SoC bars at "port of entry" shows an U.S. delivery LEAF delivered with 50% state of charge:
Battery specs: dimensions, voltage, construction, capacity, chemistry.
Battery Management System (BMS)
BMS: Secs, principles of operation, block diagram.
Nissan will manufacture the battery at a new battery plant in Smyrna, Tennessee, which broke ground on May 26th, 2010. The plant will come on at the end of 2012 and will make 200,000 battery packs a year .
2012 LEAFs will come with a battery heater as standard. Here is a
diagram of the battery heater, from 2012 LEAF service manual: 1-6, 8, and 9 are heaters, 7 is the heater relay unit :
- A green.autoblog.com article citing Nissan's Mark Perry, on LEAF's battery pack's thermal management:
"Nissan's director of product planning for the U.S. Mark Perry responded by saying:
We don't need thermal management for the U.S., but we are looking at the technology for Dubai and other locations like that.... We've gone on the record saying that the pack has a 70 to 80 percent capacity after 10 years."
- 12V battery alternative : Elite Power's "BS-LFMP40AH (4-cell pack)":
- Nominal Voltage: 12.8V (4X3.2V)
- Nominal Capacity: 40 Ah
- Chemistry: LiFeMnPO4
- Operation Voltage Range: 11.2 to 14.4V
- Weight: 6.6 kg or 14.6 lbs
- Dimension: 125X208X180 mm or 4.9X8.2X7.1 in
- Max Charging Current: 3C
- Max Discharge Current: 3C (continuous) / 10C (pulsed)
- Cycle Life : >2000 (80%DOD)
- Operating Temperature: -20 to 65 C or -4 to 149 F
- Self Discharge Rate: <3% monthly
- Accessories included: jumpers, bolts or rivets, washers, split washers and cell covers
Battery Temperature Gauge
The Li-Ion battery gauge is a 12-segmented gauge with very coarse granularity. Below are the battery temperature ranges that may be indicated by a given number of bars. The specific values shown are interpolations done by RegGuheert from a graph in the service manual. Note that there is a great deal of overlap. Consider, for example, a battery temperature of 80 degrees Fahrenheit. This could be displayed as 5, 6, or 7 bars. Nissan explains this by stating that the number of segments is corrected "according to the battery capacity."
It is unclear from their description how the correction is applied, or in which direction. It has been hypothesized that the low end of the range would apply to a new battery and the high end to a degraded battery, but this has not been confirmed. It has also been suggested that the LEAF may be estimating the temperature inside the cells with a crude thermal model, and adjusting the estimate based on known degradation. This would imply that a new battery would be at the high end of the range.
Battery Gauge Segment / Temperature Chart:
|Segments||Min Degrees C (F)||Max Degrees C (F)|
|11||52 (126)||59 (138)|
|10||49 (120)||56 (133)|
|9||47 (117)||52 (126)|
|8||36 (97)||49 (120)|
|7||23 (73)||47 (117)|
|6||10 (50)||38 (100)|
|5||-3 (27)||27 (81)|
|4||-5 (23)||15 (59)|
|3||-8 (18)||4 (39)|
|2||-12 (10)||2 (36)|
|1||-15 (5)||-2 (28)|
As one can see, segments 4 through 7 can potentially cover a very wide range of temperatures from -5C to 47C. The top 2 segments and bottom 2 segments are colored red and blue respectively to indicate very high and very low battery temperatures. It is recommended to NOT quick charge the battery when the battery is in the red zone .
Battery capacity loss stuff has been moved to this page.
- Joint study by Saft America Research & Development Center and the Jet Propulsion Lab of DD-size Li-Ion batteries for use in the Mars Rover mission. The batteries have LiNiO2 cathode, graphite anode, with Li LiPF6 electrolyte. The study documents discharge and cycle life performance at 25'C and -20'C, battery capacity loss at 25'C at 30% depth of discharge (DOD) and 60% DOD. (Document is also available here: File:JPL Saft Li-Ion Mars Rover battery study 00-1361.pdf.)
- Some information on the battery pack's cost:
- Excerpts from businessweek.com article, May 14, 2010:
"Nissan Motor Co., which will start selling its Leaf electric car this year, aims to cut the cost of the vehicleâ€™s lithium-ion battery pack to less than $370 per kilowatt-hour to make a profit from the model." (US$8,928)
"Nissanâ€™s battery currently costs about 1.05 million yen, or $472 per kilowatt-hour, according to Takeshi Miyao, an analyst in Tokyo at auto consulting company Carnorama." (US$11,328)"
- green.autoblog.com article:
"A couple weeks ago, the Times of London reported that the battery in the Nissan Leaf cost the automaker around $9,000 to produce.
"Mark Perry, Nissan's chief product planner for North America, tells The Wall Street Journal that the actual cost is a little less than $750 per kilowatt hour, bringing the total to just below $18,000."
- Excerpts from businessweek.com article, May 14, 2010:
- LEAF display showing "turtle" warning ("very low battery" warning)
Real-World Range/Power Consumption Experience
- Table showing expected range given number of "fuel bars" and speeds between 35mph and 75mph
- motortrend.com reported a range of 73 miles from a "lead-footed test drive".
(Road test is saved here.)
- 80% charged, 50 miles @ highway speed -- barsad22
- 80% charged, 60 miles @ 65 mph, no climate control -- mwalsh
- 100% charged, 70 miles @ freeway speed -- DaveinOlyWA
- "...an easy 100+" miles, eco mode, driving carefully, using AC or heater some -- PaulScott
- Max of 90 miles, average about 70-75 miles.
- 3.6, 6.5 m/kWh, 3.1 m/kWh, 3.9 m/kWh, 3.2-3.4 m/kWh ("'climate challenged' and often doing 70mph), m/kWh.
Battery Capacity Behavior
- The twelve smaller segments at far right of the battery gauge represents the battery's current maximum capacity. As the battery's capacity degrades, these bars disappear one by one. This table shows the approximate battery capacity represented by each bar :
|Segments||Retained capacity (%)||—||Note|
|12||85 or more||T12||—|
|11||85||T11||Value at which segment 12 turns OFF|
|10||78.75||T10||Value at which segment 11 turns OFF|
|9||72.5||T9||Value at which segment 10 turns OFF|
|8||66.25||T8||Value at which segment 9 turns OFF|
|7||60||T7||Value at which segment 8 turns OFF|
|6||53.75||T6||Value at which segment 7 turns OFF|
|5||47.5||T5||Value at which segment 6 turns OFF|
|4||41.25||T4||Value at which segment 5 turns OFF|
|3||35||T3||Value at which segment 4 turns OFF|
|2||28.75||T2||Value at which segment 3 turns OFF|
|1||22.5||T1||Value at which segment 2 turns OFF|
|0||16.25||T0||Value at which segment 1 turns OFF|
- Battery range dropping from 17 miles to zero in 5 miles!
- In case of a collision (air bag deployment, etc.) or certain system malfunctions, an emergency shut-off system shuts off the high voltage from the Li-ion battery. 
- LEAF service plug and the 225 amp fuse in it:
The LEAF has a 12V battery, also known as the "housekeeping battery". It performs the following functions:
- Initial switching of main battery power. Since the 12V battery supplies power to "switch on" the main battery, a LEAF with a dead 12V will not start and will have to be jump started, that is, it has to receive 12V power from an external supply.
- Initialization of the charging process.
- Providing power to 12V accessories such as the entertainment and navigation system, lighting, horn, warning chimes, etc. because it is not efficient to "step down" the main battery voltage to 12V to power these low-current-draw accessories.
The 12V battery is automatically charged when:
- On power on, the VCM determines that the 12V battery's voltage is too low .
- When vehicle is left for a long period of time: the VCM keeps track of the no-operation duration with its internal timer. If the no-operation duration reaches 120 hours, the VCM automatically charges the 12V battery for 5 minutes. The VCM resets the no-operation time when the vehicle satisfies one of the following conditions :
- The vehicle is in READY state (green "car with arrows" icon) more than 5 minutes.
- Normal charging has continued for more than 5 minutes.
- Quick charging has continued for more than 5 minutes.
- Timer air conditioning or remote air conditioning has continued for more than 5 minutes.
Medium to Long-Term Storage
12V Battery Storage
The relatively high power draw of the LEAF's electronics in standby mode and the VCM's periodic charging function during prolonged non-operation lead to substantial battery cycling that is very stressful for the 12V lead-acid battery. Leaving the LEAF plugged in leaves more computer systems running which result in a higher load on the battery, so do NOT leave the car plugged in if leaving the car for more than a couple days, otherwise you are likely to return to a dead car that needs a jump-start. For storage longer than a couple weeks, it is recommended to maintain the 12V battery charge with a Battery Tender or equivalent.
HV Battery Storage
The owners manual recommends charging the car in long-life mode (80%) and storing the car that way. But the general consensus is that storing the car with a SOC between 40-50% (4-6 bars) is even better for maintaining battery capacity. In general, storage of lithium batteries above 40% SOC results in an increase in capacity loss over time. DO NOT STORE YOUR LEAF FULLY CHARGED, ESPECIALLY IN HOT WEATHER! Storing lithium batteries fully charged and at high temperatures causes the fastest rates of capacity loss over time.
The LEAF will not lose any significant charge even when stored for months, especially if the 12V battery is disconnected.
- Enginer makes range-extender batteries that add 4 kWh, 8 kWh, and (soon) 12 kWh.
Note: It appears that Enginer has apparently gone out of business.
LEAF with Enginer 4 kWh range extender battery:
LEAF with Enginer 8 kWh range extender battery:
- http://green.autoblog.com/2010/05/27/details-on-nissan-leaf-battery-pack-including-how-recharging-sp/ "Details on Nissan Leaf battery pack, including how recharging speed affects battery life"
- http://www.nissanusa.com/leaf-electric-car/index?intcmp=.Electric_Car_Reserve.Promo.Homepage.Home.P2#/leaf-electric-car/faq/top/range Nissan LEAF FAQs
- Nissan LEAF Service Manual April 2011 revision, page MWI-21
- Need reference.
- Nissan LEAF Service Manual, page MWI-23
- http://www.nissan-techinfo.com/refgh0v/og/FRG/2011-Nissan-LEAF-FRG.pdf 2011 Nissan Leaf First Responder's Guide, page 10
- Nissan LEAF Service Manual, page EVC-45
- Nissan LEAF Service Manual, page EVC-45