Talk-Polywell.org

I found this while looking around the net. Is this new? Full charge in 5 minutes, power a motorcycle 0-60 in less than 1 second, 10 year lifetime, MIT technology, ideal for hybrid or plug in vehicles ...

http://www.a123systems.com/a123/technology

Click on the tabs to find the technical data.

I haven't heard of this company, but Toshiba is using that MIT technology here: http://www.toshiba.com/ind/

It's actually going to market (no EESTOR vaporware).

Renewable types are wetting themselves over it. Can't blame them. The nano-scale route is a game changer for batteries.

Mixed reviews of available batteries on Amazon; apparently still some production problems compounded by service problems.

The MIT patents for nanotube capacitor tech has me the most hopeful.

No toxic electrolyte, nearly unlimited lifespan, nearly instant recharge.

Aero wrote:I found this while looking around the net. Is this new? Full charge in 5 minutes, power a motorcycle 0-60 in less than 1 second, 10 year lifetime, MIT technology, ideal for hybrid or plug in vehicles ...

http://www.a123systems.com/a123/technology

Click on the tabs to find the technical data.

I can tell you A123 is well established in RC planes community. The well known properties established by long experience are:

- storage capacity per weight is slightly lower than LiPo technology, which means it is much higher than NiMh (2x).

- discharge currents are little bit better than LiPo (which means they are very very high, you can get as much as 60A from 1Ah battery)

- maximum charge currents are MUCH better than LiPo, usually you can only charge LiPo at 2-3C, while 10-20C is not a problem for A123

- A123 durability is much better. A123 have no tendency to explode and while regular LiPo survives for 50-100 cycles, A123 can go 1000.

- in the past, the price of A123 was similar to LiPo, but over years, LiPo prices are going down, so in fact, today for RC flying, LiPo has better price. Plus, only 2 types of A123 cells are available, while LiPo comes in many forms.

- any microprocessor controlled acu charger worth of its name, used by RC modellers, has a special program for A123 cells.

The energy density is low. 2 Whr/kg roughly.

I may be in error. Correct me if I'm wrong.

MSimon wrote:The energy density is low. 2 Whr/kg roughly.

I may be in error. Correct me if I'm wrong.

91.6 Wh/kg
http://www.fmadirect.com/support_docs/item_1229.pdf
Interesting comparison with LiPo

A123 is claiming quite a bit better than that, or are they? see this tab. These marketing ads are confusing.

http://www.a123systems.com/a123/products

ANR26650M1A: The ANR26650M1A is A123Systems’ pioneering product, originally designed for a new class of power tools. Applicable to a wide variety of system designs and currently in mass production, the 26650 cell offers excellent price-performance.

* Power: Over 3000 W/kg and 5800 W/L
* Safety: Excellent abuse tolerance and environmentally friendly
* Life: Excellent calendar life, 10X cycle life vs. conventional lithium ion


Our batteries use a new type of cell construction based on a dual plate tubular design optimized to deliver very high power with high efficiency. This new design does not use crimp seals and instead opts for a more advanced “all laser welded” construction optimized for very low humidity penetration over the life of the battery as well as stronger, thicker dual plate headers.

More claims. Just what does it mean to a battery customer?

# Nominal voltage: 3.3V
# Nominal capacity: 2.3Ah
# Core cell weight: 70 grams
# Internal impedance: (1kHz AC) 8 mΩ typical
# Typical fast charge current: 10A to 3.6V CCCV
# 70A continuous discharge
# 120A, 10 sec pulse discharge
# Cycle life at 10C discharge, 100% DOD: over 1,000 c

Aero, none of those parameters is "energy density Wh/kg."
Are you confusing Wh/kg with W/kg ?

BenTC wrote:Aero, none of those parameters is "energy density Wh/kg."
Are you confusing Wh/kg with W/kg ?

Well, not confusing them, I just don't see Wh/kg given anywhere. Is there a way to calculate energy density from the data given?

3.3V*2.3Ah/0.07kg = 108.4Wh/kg

Due to voltage decline during discharge, the actual value is probably a bit lower.

A123 Systems has been producing commercial batteries for nigh onto a decade now. They are popular with RC hobbyists and are the basis of one of Black and Decker's rechargable tool lines.

Their batteries keep getting better. They are now producing some fairly large cells intended for vehicular uses.

They've been an interest of mine since I saw an article in Discover Magazine all those years ago.