Panasonic Develops 1.5 kWh Li-ion Battery Module; Targeting Home Storage and Vehicle Applications
01 October 2009
| Panasonic module. Click to enlarge. |
Panasonic Corporation has developed a 1.5 kWh battery module from 18650-type (18 mm in diameter x 65 mm in length) lithium-ion battery cells to provide energy storage solutions for a wide range applications. Multiple units can be connected in series and/or parallel to store energy generated by home-use photovoltaic (PV) systems and fuel cells or power electric vehicles (EV), the company suggests.
The module has a volume of approximately 7 liters and weighs 8 kg. Voltage is 25.2V with a capacity of 58 Ah. A prototype will be shown at CEATEC JAPAN 2009 (Makuhari Messe, 6-10 October 2009) and New Energy Industry Fair Osaka (Intex Osaka, 7-9 October 2009).
The high-energy module is constructed from 140 18650-type lithium-ion battery cells—seven serially connected rows with each row made of 20 parallel connected battery cells. This structure allows for avoiding serious loss in the system performance such as system shutdown even if some individual cells fail, Panasonic says.
To build the module, Panasonic employed a high-capacity and high-durability cell technology using its proprietary nickel-based cathode material (LiNiO2). Other technologies used include its cell safety technology that uses a heat-resistant metal oxide insulating layer between the positive and negative electrodes to prevent short circuits and thermal runaway which can be caused when foreign particles get mixed into the battery cell. The new module also uses Panasonic's design technology to ensure reliability by minimizing the effects on power supply if a trouble occurs in some of the cells contained in the module.
Panasonic holds 38 patents in Japan and 22 in other countries including pending applications on the new module.
Resources
Development of High Specific Power Lithium Ion Batteries (Matsushita Technical Journal, August 2006)
So, 187 Whr/kg...but how much of that is usable if one wants to maintain long service life? 60%? Let's say 60% of 1.5 Kwhr or 900 Whr, or about 4.5 miles of driving distance...or about 0.55 miles/Kg of battery pack.
...I guess that's closer to closer to a reasonable distance for a reasonable amount of mass. How does this compare to the Tesla's battery pack?
Posted by: HealthyBreeze | 01 October 2009 at 12:14 PM
cool, how much will it cost? Throw 10 of those together in your old beater and you can convert to a decent electric car.
Posted by: Mark_BC | 01 October 2009 at 12:14 PM
I am assuming there is some type of Battery Management System - Would be good to know what it does.
Posted by: citizen | 01 October 2009 at 12:48 PM
Modularity (with 6+ 1.5 to 5 Kwh modules) may be the way to match e-storage size to individual requirements. Efective electronic battery pack management should not be a major challenge.
Overall energy density of 187 Wh/Kg is not that bad considering the early development stage. Sion Power, Hithachi, Li-Tec, Electrovaya and a few others claim more (up to 330+ Wh/Kg) with different tecnologies.
Energy densities of up to 450 Wh/Kg is on the horizon and will be around by 2014/2015.
Interesting decade ahead.
Posted by: HarveyD | 01 October 2009 at 01:50 PM
HealthyBreeze,
Q&D - Panasonic 1.5kWh:8kg, Tesla 53kWh: 450kg -> 35.33 times larger power.
Pan.. 140 cells x 35.33 = ~5000 vs 6800
Pan.. 8kg x 35.33 = 283 kg -> 63% of weight(w/batt. mgt?), but without price info as usual.
Posted by: kelly | 01 October 2009 at 05:21 PM
@ Kelly,
Second that :-P on no price info.
35.33 x 4.5 miles per Panasonic module = 156 miles/charge ...but I've made some big assumptions about the 200 Wh/mile and the 60% of storage usable without impacting battery life.
Posted by: HealthyBreeze | 01 October 2009 at 05:32 PM
HealthyBreeze,
The Tesla pack works out at 120 Wh/kg. But there are more things than just energy density.
The maximum charge current for these Panasonic cells is 0.7C, so the minimum charge time of this pack is ~1.5 hours. The Tesla pack offers faster charge (45 min to 80% I believe).
The Tesla pack is optimized for high power. That means it needs good cooling. And it has heating too, for (very) cold weather. I do not know what maximum power this Panasonic pack can deliver. But the cooling/heating system in the Tesla pack certainly adds weight.
Here is an example of these Panasonic NCR 18650 cells on sale for $8 a piece (in quantities of >200): http://www.alibaba.com/product-gs/250816129/Panasonic_18650_Battery_NCR18650_2900mAh.html. That works out to 140 x $8 = $1120 worth of cells.
Posted by: Arne | 01 October 2009 at 11:38 PM
This technology rocks. With allowances for packaging, cooling, BMS and 80% DOD. a 25KWh pack should be comfortably below 200Kg
Price is what Panasonic can negotiate with the buying party. How much are you prepared to pay to displace gasoline?
Manufacturing costs get more competetive as energy density increases. The raw materials, precursors and production costs diminish roughly in proportional to increase in energy density.
I'd stick my neck out and estimate they could produce these sub $150 per KWh with 1,000,000 units/ anum.
Posted by: Carlos Fandango | 02 October 2009 at 12:09 AM
HealthyBreeze,
Another thing I forgot to add. The usable capacity. You are right that it is preferable to keep it within 60%.
But think about real life. Assume you have a car with a 50 kWh pack, offering a (theoretical) 300 km range. The daily commute is usually less than 100 km. So for that, you only need ~33% of capacity, assuming you charge your car every night. The occasions that you need the maximum range are exceptions. Using 80% or more of the capacity once in a while won't seriously shorten the life of your battery.
The Tesla Roadster has this wisdom incorporated in the design. By default the pack does not charge fully. There is a special button to do so. If you know in advance you are going to make a long trip you can charge it to maximum, sacrificing a tiny fraction of battery life.
The usage pattern of an EV is different from a petrol car. You don't have to pay a visit to a petrol station to 'fill it up', instead you plug it in every night when you come home. Range is less of an issue in most cases.
For those interested, here are some discharge curves for these NCR 18650's.
Posted by: Arne | 02 October 2009 at 12:14 AM
An interesting development for small business PV storage systems. How much would a 15kWh system with power management cost? According to Anne's current cell pricing, around $12k. Too high for home PV but moving in the right direction.
Posted by: Reel$$ | 02 October 2009 at 03:29 AM
This also turned up on October 1.
Notice the "half the cost" bit....
"Panasonic Corp said on Thursday it has developed a technology that binds together standard lithium-ion battery cells used in laptop PCs to power electric vehicles, taking aim at growing demand for green cars.
The new technology will likely enable Panasonic to make electric car batteries at half the cost of lithium-ion batteries that are developed solely for electric cars, since it can use existing battery plants and production expertise, the company said."
http://www.reuters.com/article/rbssConsumerGoodsAndRetailNews/idUST21755220091001
Posted by: Bob Wallace | 02 October 2009 at 08:45 PM