As a drop-in replacement for 180- by 124- by 198-mm (U1) sealed lead-acid (SLA) batteries, the maintenance-free, 12-V, lithium-iron-phosphate (LiFePO4) Ironworks battery packs from Micro Power Electronics offer long runtime (40-Ah), fast charge time, (two hours at 20 A), long shelf life, and light weight (6 kg).
LiFePO4 is a relatively new lithium-cathode material made practical by a combination of fine granulation, doping, and coating developed at the Massachusetts Institute of Technology. At this time, the most attractive use of these batteries is in hospital and clinic medical-diagnostic-equipment carts, where their total-lifetime cost savings are immediately apparent.
In other words, they may cost more than SLA batteries, but they offer longer cycle-life in addition to longer runtime, faster charge time, and longer shelf life. The Ironworks packs also can be charged with the same chargers that SLA batteries use, and they incorporate fuel gauging and battery status reporting via SMBus ports. When they do need to be swapped out, their light weight relative to SLAs is attractive as well.
Although their initial market focus is medical, including portable infusion pumps, ventilators, wheelchairs, and workstation carts along with roll-around diagnostic equipment, in the long run, Micro Power Electronics expects them to penetrate the personal mobility, electric bicycle, and general power backup markets.
Ironworks batteries (see the figure) are UL 1642 certified and were designed to meet UL 2054 safety standards. They are UN/DOT shipping-approved and comply with the European Union’s Restrictions on Hazardous Substances (RoHS).