How long is a lithium-ion battery expected to last in a UPS application?
Eaton’s vendors expect 10-15-year float service life like we utilize in our UPS equipment. Both vendors offer a 3-year defect warranty and a Performance warranty of 10 years.
What is the shelf life of lithium-ion batteries before they need to be checked or charged?
If the lithium-ion battery modules are connected together, i.e. installed in a cabinet, the storage times are six months at 25 degrees C. This is due to parasitic losses from the BMS. If the battery modules are NOT connected together (either power or communication connections), then the storage times are one year at 25 degrees C. Note: Samsung requires a "voltage check" of the batteries every 180 days during storage.
Are there different recharge rates between lithium-ion and VRLA batteries?
Lithium batteries can be recharged significantly faster than traditional UPS batteries; however, keep in mind that the manufacturers limit the amount of battery charge current that the UPS can supply. During recharge, the BMS monitors not only voltage levels, but also the internal temperature of each individual lithium cell. In this manner, the system will automatically limit the charge if a cell gets too warm, which can potentially lengthen the recharge time. In general, the VRLA rule-of-thumb of “10x the discharge time to 90 percent capacity” may not apply to lithium.
How long does it take to return a lithium-ion UPS battery to 90% capacity after a discharge?
At the vendor-specified recharge currents, it should take no more than 4 hours.
What are recycling protocols regarding lithium-ion vs lead acid?
Eaton has partnered with Call2Recyle to lead the charge in recycling end-of-life battery packs. We provide consumers across North America the capability to do the right thing and conveniently recycle used lithium-ion batteries
versus throwing them in the landfill.
Do lithium-ion batteries have recycling and/or disposal issues?
Lithium-ion batteries are disposable and, while currently not readily recyclable, new options are expected in the future. To read more about recycling lithium-ion batteries, visit Eaton's battery recycling
Are there kWH capacity restrictions for lithium-ion battery installations?
Yes. IFC 1206 and NFPA 855 state that maximum allowable quantities are 600 kWH per room, unless the room is specifically built for H2 Hazard Class occupancy. This can be waived by the Authority Having Jurisdiction (AHJ) in the presence of UL9540A test results and a FEMA analysis by engineers designated by the building owners.
Is there any difference between sizing a lithium-ion battery compared to VRLA or NiCd technology?
Yes, the sizing is slightly different and in the case of lithium, we limit the backup time based not only on low cell voltage limits, but also the cell temperature during discharge. This means the cutoff time for a lithium battery might be dictated by high temperature, as opposed to only low voltage. Eaton’s published battery time tables for our UPS products take this into account, and our application engineers are trained on proper sizing of these batteries. As always, feel free to contact Eaton
for sizing guidance.
Are there any issues with recharge current after an EOD due to lower resistance in lithium-ion batteries?
At this time, Eaton uses vendor-specific battery charge current limits for lithium-ion UPS systems. These are expected to change over time as we deploy more lithium-ion batteries in traditional UPS system applications and, therefore, gain more data to base our battery charge current limits on. For now, the vendor-specific limits represent a pretty conservative estimate.
Should recharging lithium-ion UPS batteries be delayed after a full discharge?
No. We have limited the charge current per cabinet to a level that will not add internal heating to the battery, thus we can begin recharging immediately upon return of input power.
Can the lithium-ion UPS batteries be charged by the PhotoVoltaic (PV) system, assuming the current is suitable? If not, what other back-up method would you suggest?
We recommend that the PV system, most commonly known as a solar power system (and its inverter) be fed to the UPS input so the UPS directly controls the battery recharging. In the future this may not be necessary, but currently it is important to have control over the rate of charge for the UPS batteries.
Do lithium-ion batteries work with Eaton ABM?
is not needed with lithium-ion batteries. The purpose of ABM is to extend the service life of VRLA batteries, and since lithium-ion already has an excellent service life characteristic, there are no immediate plans to use it.
Are the float charging requirements for new lithium-ion battery cabinets different than those for older UPS systems with VRLA batteries or flooded cell batteries?
Yes. The float voltages and ranges for lithium-ion batteries are slightly different. This is handled by a trained CSE in the UPS firmware settings at the startup time.
What are the BTUh numbers when float charging lithium-ion UPS batteries?
See the Eaton customer drawings for BTUh levels. This heat is negligible.
Download the Samsung lithium-ion drawing here. Download the LG Chem lithium-ion drawing here.
What are the BTUh levels during discharge of lithium-ion UPS batteries?
Worst case, 8900 BTUh for Samsung, and only during the duration of the discharge. We do not have this value for LG Chem, but it is expected to be similar.
Why is electrolyte weight important for lithium-ion batteries for UPSs?
Building Codes require the room to become ‘incidental occupancy’ with 1-hour separation rating for the lithium ion/UPS battery room, if total electrolyte weight is >1000 lbs. The battery room shall not be more than 10% of the total building area, in the story they are located.
What is the electrolyte weight of Eaton’s lithium cabinet systems?
|LG Chem half cabinet
|LG Chem full cabinet
How are lithium-ion UPS batteries shipped? Can they be air shipped?
We will ship battery cabinet systems by ground. Individual replacement batteries may be air shipped. Refrigerated ground shipment is not required for either vendor. Shipments must be in accordance with UN38.3 requirements. All shippers must be trained on Class 9 shipment of hazardous goods. These requirements involve specific packaging, labeling of said packaging, and accompanying paperwork. Trucker and the truck must be certified with proper signage. Batteries for air shipment must not exceed 30% state of charge (SoC). We will ship all lithium batteries at 30% SoC, whether ground or air shipment. It will require about 4 hours of charge time to bring the newly replaced battery up to full charge Battery cabinet systems are shipped disassembled. All assembly and start-up/commissioning activities are included in our pricing.
What are lead times for UPSs with lithium-ion batteries?
4 to 6 weeks from stock (systems must be kitted prior to shipment)
Can copies of Installation and Operators’ Manuals be provided in advance?
Yes, these are available in advance for Eaton sales support. However, they may not be shared. The vendors’ intent is that the user utilizes only the up-to-date manuals that ship with their cabinets. Eaton’s customer installation drawings can be shared at any time. They are posted for both vendors on the SalesWeb. Eaton’s Guide Form specifications can be shared at any time. Guide specs and Eaton customer drawings for both vendors are available on the SalesWeb.
Can the lithium-ion battery cabinet communicate over the network?
Yes, both vendors’ lithium-ion UPS battery cabinets communicate by Modbus TCP. The customer’s connection is via a TCP/IP (RJ45) connector from the bank battery BMS module on either vendor’s cabinet/system.
NOTE: The Modbus TCP provides no alarm history. Information is real time, unless the user creates an external logging program.
Will PredictPulse eventually be connected to lithium-ion battery cabinets?
Yes. Eaton is working to make lithium-ion UPS battery cabinets compatible with PredictPulse monitoring service
, with all pertinent information and data monitored and logged.
Is user monitoring software available for lithium-ion battery cabinets?
No, clients must use Modbus TCP which is built-in for both vendors.
How do Eaton systems deal with dendrites in lithium-ion batteries?
The lithium cells in our lithium-ion battery units are composed of LFP (lithium iron phosphate). Each cell includes built-in over charge protection, pressure vent, anti-puncture ceramic coating, and a barrier on the positive LFP electrode to help mitigate short circuiting from any dendritic growth. Also, our BMS monitors and controls every cell within the battery pack to mitigate conditions which may encourage dendrite growth.
For more information on dendrites in lithium-ion batteries, read Eaton’s latest application note.
What is max room temperature for lithium battery UPSs?
Operating temperature range: 32 to 104°F / 0 to 40°C