ELiTE Battery Information

ELiTE Battery Information

History of Li- Ion Batteries What is a Lithium-ion Battery? Two or more electrochemical cells, electrically interconnected. Each cell contains two electrodes and an electrolyte. The reaction that occurs at these electrodes convert electrochemical energy into electrical energy. Lithium & Lithium-ion Batteries Lithium is a metal with a very low density and has the greatest electrochemical potential and energy to weight ratio. It belongs to the alkali metal group of chemical elements. Under standard conditions it is the lightest metal and the least dense solid element. Like all alkali metals, lithium is highly reactive. The low atomic weight and small size of its ions also speed diffusion. Experimentation with lithium batteries began in 1912 under G. N. Lewis. It wasn t until the 1970 s when the first lithium batteries came onto market. The first cells developed were 3V cylinder and 3V button type. They are still widely used in small equipment and medical devices today. Many developments in technology occurred in the 1980 s. American chemist, John B. Goodenough began experimenting with Lithium Cobalt Oxide as a cathode (positive lead) material. A Moroccan research scientist, Rachid Yazami discovered graphite as an anode (negative lead) material. These developments led researchers to build the first lithium-ion battery prototype in 1985. The Sony Corporation commercialized the Li-ion battery in 1991. In 1997 lithium battery materials and manufacturing changed allowing them to be shaped to fit a particular device. In 1999 the lithium nickel cobalt aluminum oxide battery was developed. This is the type used by Textron Specialized Vehicles and many other EV manufacturers. John B. Goodenough was nominated in 2016 for a Nobel Prize for his accomplishments in lithium ion technology. Today, the Lithium battery technology continues to develop and evolve to provide greater performance and reliability. Source: Wikipedia Page 1

Where does Lithium come from? What else is it used for? Source: Wikipedia Page 2

Construction of Li-Ion Batteries Lithium-ion Cells As with most lithium-ion batteries, you have an outer case made of metal and has a pressuresensitive vent hole. The cells normally do not gas, however if the battery gets so hot that it risks damage from over-pressure, this vent will release the extra pressure. Major temperature changes (thermal shock) can cause a small amount of cell gassing. The vent is strictly there as a safety measure, as well as the Battery Management System (BMS), a device that is designed to protect the battery cell modules. Page 3

Construction of Li-Ion Batteries This metal case holds a long spiral comprising three thin sheets pressed together: A Positive electrode A Negative electrode A separator Inside the case these sheets are submerged in an organic solvent that acts as the electrolyte. The separator is a very thin sheet of microperforated material. As the name implies, it separates the positive and negative electrodes while allowing ions to pass through. Page 4

Construction of Li-Ion Batteries The positive electrode is made of Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAlO 2 ). The negative electrode is made of Carbon. When the battery charges, ions of lithium move through the electrolyte from the positive electrode to the negative electrode and attach to the carbon. Normal temperature increase during charge is around 3 5 degrees Celsius. During discharge, the lithium ions move back to the LiNiCoAlO 2 from the carbon. The movement of these lithium ions happen at a fairly high voltage, so each cell produces 3.7 volts. Li-ion batteries build a small amount of heat during discharge. Flooded lead acid batteries also build heat during discharge, however the temperature does not rise significantly due to the lead acid battery s thermal mass. The BMS and the battery charger work together to limit temperature. Sensors turn the BMS off if temperatures are out of range. Source: Howstuff works & TSV Page 5

Construction of Li-Ion Batteries Each battery module contains the individual cells. There are 14 cells connected in series X 13 cells connected in parallel to equal 182 individual cells in each module. Once installed in a vehicle, additional battery modules cannot be added to an existing set to increase capacity. The high capacity modules must be ordered as a set from the factory. Page 6

Construction of Li-Ion Batteries The Lithium nickel cobalt aluminum oxide battery, or NCA, has been around since 1999 for special applications. It shares similarities with NMC (Lithium Nickel Manganese Cobalt Oxide) by offering high specific energy, reasonably good specific power and a long life span. NCA is a further development of lithium nickel oxide; adding aluminum gives the chemistry greater stability. Lithium Nickel Cobalt Aluminum Oxide: LiNiCoAlO 2 cathode (~9% Co), graphite anode Short form: NCA or Li-aluminum. Since 1999 Voltages Specific energy (capacity) Charge (C-rate) Discharge (C-rate) Cycle life Applications Comments Weight 3.60V nominal; typical operating range 3.0 4.0V/cell 200-260Wh/kg; 300Wh/kg predictable 0.2C, charges to 4.0V (most cells), 4-5h charge typical at max DOD. 56V is max pack voltage. 1C typical; 3.00V cut-off; high discharge rate shortens battery life. Max current draw is 300A. Warranted for 5 years regardless of AH used. Medical devices, industrial, electric powertrain (Tesla) Shares similarities with Li-cobalt. (BMS) Master module and two cell modules weigh 65lbs. NCA Battery performance compared to other battery types. Source: Battery University Page 7

Battery Management System (BMS) The battery management system is also known as the BMS module. It s primary function is to maximize energy efficiency between cells and to provide protection for the battery modules. The circuitry inside the BMS communicates with the battery modules and the electronic speed controller on the vehicle. Cell temperature, cell voltage, and current are monitored by the BMS module. It prevents excessive discharge and too much overcharge. A contactor is installed in the module to open and close based on vehicle and battery conditions. A 400 amp fuse is placed in the BMS module to protect the battery management system in case of short circuit. The circuit board in this module is protected by a 5 amp fuse. The BMS module can only be serviced by the battery manufacturer. The warranty is void if the BMS seal is broken. Do not disassemble the BMS! The BMS module is IP65 rated which means it is water resistant, but not water proof. Care should be taken not to flood the BMS or battery modules with water. Do not turn the vehicle ignition on if the vehicle has been submerged. Disconnect the BMS and battery modules immediately. On-board diagnostics are provided by the BMS module. Diagnostics are accessed using the Curtis 1313 hand held tool or the Battery Diagnostic Tool with the Smart phone app. Page 8

Charging Page 9

Charging Page 10

Charging Ammeter Displays scale of output current If only ammeter and AC indicator lights are lit: less than 80% charge. If flashing: Output has been reduced due to high internal charger temperature. The 5 bar light indicates normal charge. The 6 bar light is not used. Charge Indicator (Orange light) If solid: Greater than 80% charge. Charge Completion Indicator (Green Light) If solid: Charge is complete. AC Indicator Light (Orange Light) If solid: AC is present. If flashing:: Low AC voltage. Check electrical source and cord length. Fault Indicator (Red Light) Charge error. Refer to trouble shooting info below. Page 11

Current C 18 16 14 12 10 8 6 4 2 0-2 Charging Algorithm FC6 at 15 C 1 151 301 451 601 751 901 1051 1201 1351 1501 1651 1801 1951 2101 2251 2401 2551 2701 2851 3001 3151 3301 3451 3601 3751 3901 4051 4201 4351 4501 4651 4801 One reading every 3 seconds 58 56 54 52 50 Volts 48 46 44 42 Current Temperature Voltage Discharge limit 43.5 Amp Hours out 50.84 Amp Hours in 52.47 Full Charge time 4.0 hours Other charging info: The AC draw is 8A. Use a dedicated 10A breaker per charger. Operating voltage range is 42V to 56V. Allow the charger to turn off on it s own. If the charge cycle is to be interrupted; unplug the AC cord first then the DC. There is a 3 second delay before the charger will turn on. This delay can be up to 2 minutes. Wait for the charger light. Wait for the receptacle light. Listen for the click. The battery charger will not turn on if the cell temperature is above 60C 140F. The BMS prevents charging below -10 C and above 60 C (Cell temps, not ambient). Between - 10 and 5 C, and between 45 and 60 C, charging proceeds at a slow rate ( 6 amps). Between 5 and 45 C, full charging is allowed ( ~14 Amps). The charger and BMS automatically set the charge rate, and the rate will update automatically as the cell temperature changes. Li-Ion batteries do not have a memory so charge cycling is not required. They are delivered at 30% capacity. As with other new Li-ion battery products; charge the vehicle one full cycle before use. Do not leave the charger plugged in during long term storage. Replace the cell modules if voltage drops too low to turn the charger on. Set the Run / Tow switch to the Tow / Storage position on TXT models. Set the Run / Tow switch to the run position on RXV models. Page 12