What about that new fangled carbon fibre stuff - better make sure they put double the amount of that on or perhaps just stick with aluminium. Undoubtedly Boeing did their testing and decided the new batteries were safe and yielded significant benefits, primarily weight saving. The government approved Boeing's use of lithium-ion batteries to power some of the plane's systems in 2007, but special conditions were imposed on the plane maker to ensure the batteries would not overheat or ignite.But heck, where did that aluminium stuff come from!!?? Government inspectors also approved Boeing's testing plans for the batteries and were present when they were performed. It has a constant-current, constant-voltage (CC/CV) circuit.
I suspect the electrical system weights and redundancy decisions were made by MBA's, which like papal pronouncements in catholicism, are infallible in the corporate religion.Before the 787, I have never heard of any lithum-tech batteries being used for anything mission-critical in aerospace (please enlighten me if I am wrong). kæreste Høje-Taastrup As a previous poster points out: TNX, boogle Weight and form factor not a biggie.The FAA approval of Boeing's use of Li-Ion batteries is in the following document.One would expect that Boeing's testing and results will be examined against the FAA approval.
Thales single bay charger
It can be powered by USB and comes with a USB/Mini USB power adapter. will repair or replace without charge, any defects due to faulty materials or workmanship for a period of 90 days from the date of purchase.In my mind, it ain't worth the extra battery capacity to require expensive charging systems and such. Then there's the requirement to have a good fire extinguishing system if one of the suckers goes into thermal runaway.The designers probably required to use them in the 787. On maintenance aspects and risks its clear Boeing heard the promises of the suppliers (Batt and chargers) installing it close to Electronic Equipment without elaborated safety schemes in case of major failures like the ones that occurred.
Lithium-cobalt, lithium-poly and lithium-ion batteries can be very unstable even under normal conditions; only the power management chip in your laptop battery stops it from bursting into flames when charging. Enormous pressure on battery makers to increase energy density and decrease weight/volume, for phones / laptops / tablets etc. ) has resulted in increasingly daring & unstable designs being produced. The massive electric requirements of the 787 compared to other a/c only compound the problem.
Its unclear to me the size of the gain in using these batteries.
We need to understand better the trade-offs and quantify. May be the very high peak current of the new batteries (due low internal resistance) were important for the high energy consumption of the 787?
Securaplane has developed a method for accurately detecting the inflection point which has eluded battery experts for years and is critical in reducing an overcharge condition.
This patented method of charging ensures that the battery receives the optimum amount of charge for all temperature conditions combined with various battery states of charge.