powermed
10 W
- Joined
- Jun 22, 2008
- Messages
- 80
Whoops, I said 10% to the upside - should have said from 2 - 5% on the upside.
Found what I thought was all the tech stuff I'd need, a paper written by the team that brought you the prius battery...Journal of Power Sources Volume 100, Issues 1-2, 30 November 2001, Pages 117-124
Development of nickel/metal-hydride batteries for EVs and HEVs
Akihiro Taniguchi*, Noriyuki Fujioka, Munehisa Ikoma, Akira Ohta
Panasonic EV Energy Co., Ltd., 555 Sakaijuku, Kosai, Shizuoka 431-0452 Japan
Bought the download for $30 and was thrilled and disappointed - no charging details I was looking for (I emailed the company - couldn't track down the authors). On the other hand, there's clear indication the chemistry is certainly tweaked for performance and longevity.
Select quotes so I don't get beat up for copyright infringement:
"...Stable characteristics were observed without deterioration of discharge capacity after 1000 cycles...After testing corresponding to a driving distance of 300,000 km with [discharge / charging to 30% - my translation - ] there was no deterioration observed in battery performance..." From the graph both internal resistance and amp capacity did not change significantly.
"...This battery module is very safe due to its excellent resistance to over-charging and over-discharging..."
Gleaned numbers;
- Discharge Power ratings: 1000 W/kg for 10 seconds power and 1150 W/kg for 2 seconds, and at 20% state of charge the power is still very good at 800 and 1000 watts respectively
- Specific energy: 46 Wh/kg
- Internal resistance shown on a graph is 2.8mOhm / cell
- Cutoff voltage is 6.0v
"I was thinking the idea of using a laptop charger is starting to seem like a good idea. I have been looking at the IBM 16v 4.5 amp chargers. looks like you can pick them up for about $10 on ebay.Thinking 4 of them charging 2 battery's each would be fine. I was interested in the trim pot modifications to make them adjustable? Would be nice to be able to fine tune them to exactly 16.6v and dial in the amps"
Heck, you can get a lot of them for not much more than that if you scout around. I don't think there's a trim pot inside - I don't think you need one. I'm also sensing these cells don't get out of balance that easily, so I'm now leaning towards a suitable simple CVCC source like a recently purchased 36v 4A soneil - this should have a trim pot. My small 36v 1A soneil puts out just a little too much voltage - just over 42v or 8.4v per cell.
Found what I thought was all the tech stuff I'd need, a paper written by the team that brought you the prius battery...Journal of Power Sources Volume 100, Issues 1-2, 30 November 2001, Pages 117-124
Development of nickel/metal-hydride batteries for EVs and HEVs
Akihiro Taniguchi*, Noriyuki Fujioka, Munehisa Ikoma, Akira Ohta
Panasonic EV Energy Co., Ltd., 555 Sakaijuku, Kosai, Shizuoka 431-0452 Japan
Bought the download for $30 and was thrilled and disappointed - no charging details I was looking for (I emailed the company - couldn't track down the authors). On the other hand, there's clear indication the chemistry is certainly tweaked for performance and longevity.
Select quotes so I don't get beat up for copyright infringement:
"...Stable characteristics were observed without deterioration of discharge capacity after 1000 cycles...After testing corresponding to a driving distance of 300,000 km with [discharge / charging to 30% - my translation - ] there was no deterioration observed in battery performance..." From the graph both internal resistance and amp capacity did not change significantly.
"...This battery module is very safe due to its excellent resistance to over-charging and over-discharging..."
Gleaned numbers;
- Discharge Power ratings: 1000 W/kg for 10 seconds power and 1150 W/kg for 2 seconds, and at 20% state of charge the power is still very good at 800 and 1000 watts respectively
- Specific energy: 46 Wh/kg
- Internal resistance shown on a graph is 2.8mOhm / cell
- Cutoff voltage is 6.0v
"I was thinking the idea of using a laptop charger is starting to seem like a good idea. I have been looking at the IBM 16v 4.5 amp chargers. looks like you can pick them up for about $10 on ebay.Thinking 4 of them charging 2 battery's each would be fine. I was interested in the trim pot modifications to make them adjustable? Would be nice to be able to fine tune them to exactly 16.6v and dial in the amps"
Heck, you can get a lot of them for not much more than that if you scout around. I don't think there's a trim pot inside - I don't think you need one. I'm also sensing these cells don't get out of balance that easily, so I'm now leaning towards a suitable simple CVCC source like a recently purchased 36v 4A soneil - this should have a trim pot. My small 36v 1A soneil puts out just a little too much voltage - just over 42v or 8.4v per cell.
