LiFePO 4 は比較的安全なタイプのリチウム電池です。エネルギー密度（1ポンドあたりの利用可能な電力）は優れていますが、最大出力は通常2C程度に制限されます。そのため、Cレートを十分に低く抑えるには、より高い総容量が必要です（例えば、25Aのコントローラーを使用する場合、少なくとも15Ahを確保する必要があります）。[1]必要なBMSを備えた LiFePo 4 バッテリーは、非常に簡単に充電できます。これは、「プラグアンドプレイ」バッテリーに最も近いものです。
他のリチウム電池と同様に、個々のセルは直列および並列に接続され、所望の電圧とAhに達します。公称セル動作電圧は3.3V～3.0Vです。最大充電電圧は3.6V、最小電圧は2.8Vです。ほとんどのLiFePO 4 電池には、セルを安全な動作範囲内に保つためのバッテリーメンテナンスシステム（BMS）が搭載されています。充電中は、BMSがセルのバランスを取り[2] 、過充電を防止します。放電中は、BMSが総電流を制限し、個々のセルが最小電圧を下回るまで放電されるのを防ぎます[3] 。BMSの典型的な動作は、システムの過電流、電圧不足、または過電流が検出されると、電源を遮断することです。バッテリーの電源をオフにしてから再びオンにすると、BMSはリセットされます。
A123 batteries have higher discharge rates than other LiFePo4 batteries.[4] These cells uses nano technology to allow a high discharge rate of up to 17C. A123 batteries are also correspondingly more expensive.
Compared with LiPo, LiFePo4 has a higher upfront cost, however the lifespan is usually longer[5] (generally rated at 3 times the cycles of LiPo).[6] LiFePO4 has a pretty flat discharge curve that makes a battery meter hard to use.[7]
There are two common types of LiFePO4 batteries:
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Lithium Iron Liquid Electrolyte - cylindrical cells, such as A123M1 and Headway. More fault-tolerant than LiPo. Voltage range: 3.3V nominal, 3.65V to 3.7V maximum, no lower than 2.7V on deep discharge.
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Lithium Iron Polymer Electrolyte - pouch batteries, [8] such as Ping and A123.
Form Factors
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Prismatic - A hard sided rectangular package with screw terminals. Typically for 10ah and bigger batteries.
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Pouch - A flat mylar bag with flat electrodes. The lightest, least expensive and least robust format of cell.
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Round cell - Cylindrical cell with screw terminal on the ends
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18650 - A cell slightly long and fatter than a AA battery. A123 batteries are commonly available in this format.
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26650 - An A123 cell, 26 mm in diameter, 65 mm in length.
It sounds as if you are under the impression that Turnigy is one chemistry, and Zippy is LiFePO4--that's not the case. Turnigy and Zippy are just two "brands", as it were.
In case you're actually asking about which one of those brands has better LiFePO4 cells, AFAICT neither has any good ones. You would want Ping, A123, or *maybe* the Sunthing (IIRC) packs for LiFePO4. *Don't* get Vpower/Volgood/etc packs--they do work (usually) but they suck to have to fix whenever tab welds break or cells die and take the string with them, etc. :( (see my threads on repairing them for examples).
How does one actually purchase genuine A123 cells?Depends on the kind you want--becuase A123 does not sell directly to the public, (and they don't actually really exist as such anymore, either), you can't actually know *for certain* that any cell you buy as A123 actually will be. Some places, like EM3EV (cell_man here on ES) almost certainly have the real cells, in good quality, and some other places *might* have good ones, whether genuine A123 or not (like OSN)--but it is a crapshoot with most of those places in China, other than EM3EV.
これが最高級品だという意見については、まあ、それは完全にあなたのニーズ次第です。超高電流を必要としないのであれば、LG ChemやEIGのようなNMCでも十分で、しかも軽量です。少なくともEIGなら、メーカーから直接購入できるので、純正品であることが保証されています。（ただし、費用はかかりますが）
参照スレッドリンク
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=48225