OXIS Energy and Lithium Balance partner on Li-sulfur battery system for China e-scooter market; targeting spring 2018
08 June 2016
Li-sulfur battery developer OXIS Energy UK (earlier post) and Lithium Balance of Denmark are partnering to build a prototype Lithium-sulfur battery system primarily for the e-scooter market in China. Lithium Balance is a battery management expert which has supplied its BMS systems for Li-ion based e-scooters for a decade. The E-scooter itself will be manufactured in China.
The current prototype battery has a capacity of 1.2 kWh using 10Ah OXIS Long Life cells; weighs 60% less than the current lead acid battery; and delivers a significant increase in range. The next stage is to build a second prototype using an improved Long Life chemistry (up to 20Ah) which will increase battery capacity at a reduced weight.
The current 2.1V, 10Ah long-life cell features a gravimetric specific energy of 152 Wh/kg, and volumetric energy of 141 Wh/L, with a cycle life of 1,400 cycles.
Crucially, production costs will be reduced to meet the demand of the Chinese market. The timescale for this second phase is the fourth quarter of 2016.
The volume of E-scooters in China is 30 million, of which 98% use lead acid with the remaining 2% using Lithium-ion.
The development of the first Lithium Sulfur e-scooter battery system will allow Chinese manufacturers to circumvent the use of unsafe, toxic and environmentally damaging battery systems such as lead acid and Lithium-Ion. It will allow Chinese consumers to travel longer distances with a significantly greater degree of safety and flexibility and with a battery system that’s 60% lighter—the latter being very important to Chinese commuters living in high rise city apartments. In effect, the market of rechargeable lithium batteries will undergo a quantum leap forward in the adoption of state of the art renewable energy technology. This will contribute to cleaner air quality in the major urban areas of China.
—Huw Hampson-Jones, OXIS CEO
This project represents a technology breakthrough for Lithium Balance. In cooperation with OXIS Energy we have implemented dedicated BMS algorithms that optimizes the performance of Lithium Sulfur batteries. This could not be achieved with an ordinary Lithium-Ion BMS.
—Lars Barkler,Lithium Balance CEO
OXIS and Lithium Balance are on track to have their battery systems in China by the spring of 2018. This reflects the results of an existing £2-million (US$2.9-million) investment made by OXIS into new processes and production machinery in preparation for mass production of Lithium-sulfur cell technology.
OXIS Energy has been involved in the design, development and now the move towards commercial production of Polymer Lithium Sulfur cells for electric vehicle battery systems since 2004. It has been granted 79 patents with 93 pending. The chemistry and technology is inherently safe and biodegradable. OXIS says it has demonstrable empirical data justifying its claim on the inherent safety of its battery technology.
What's the point of this chemistry?
- It has low energy density.
- No mention to power density.
- Has a long life, but no longer than LiFepo4, currently used in China.
- Good safety; ok, but current Li-ion systems are very safe too.
- It has low voltage, not a good thing.
So what's the point? Price maybe?
Posted by: peskanov | 08 June 2016 at 08:35 AM
It's got pretty bad measurables in almost every way, so I'm assuming it's all about the price here?
"Crucially, production costs will be reduced to meet the demand of the Chinese market. The timescale for this second phase is the fourth quarter of 2016."
Posted by: DaveD | 08 June 2016 at 09:21 AM
Pretty sure the poor energy/power specs are to compensate for the high cycle count.
Posted by: Anthony F | 08 June 2016 at 11:01 AM
It has pretty bad energy density (kWh/L), but phenomenal specific energy (kWh/kg). Specific energy is what matters for electric flight, because you have tons of volume in wings to store batteries, but it has to make sense weight wise.
Combined with its safety, it makes sense in cars too, despite its low energy density. If you don't have to worry about it overheating, exploding on impact, or high weight density (to throw off center of gravity), you're not limited to storing them in an armored floor compartment. You can feasibly put them in door panels, ceiling panels, quarter panels, etc.
The price is nice too, because gasoline refineries will pay you to take sulfur away vs paying a premium for metals like nickel, cobalt, and manganese.
Posted by: Sublime | 08 June 2016 at 11:10 AM
Sublime,
I think you misread the article. It says:
"specific energy of 152 Wh/kg".
Barely better than LiFePo4, but half the energy density of modern Li-ion.
Also, we don't know the chemistry, wyth all the components. Maybe nickel or manganese is used too...Lithium cells are usually complex beasts.
BTW, manganese is really cheap an abundant. Nickel and cobalt are problematic, though.
Posted by: peskanov | 08 June 2016 at 11:26 AM
That's where it's at right now, but the chemistry is expected to get to 500 kWh/kg in a few years. It has a much higher theoretical limit vs NMC and NCA.
Posted by: Sublime | 08 June 2016 at 11:42 AM
Sublime,
Well, they did say that they were targeting to "double" the specific energy in phase 2. But even 300Wh/kg is not that great as the Panasonic cells in Tesla was at ~260Wh/kg 2-3 years ago.
Also, I've seen some good cases made that the energy density is actually important in vehicles, more so than many of us give it credit for.
Anyway, for the time being the price is probably the most important thing to consider as long at there is nothing wrong safety wise.
Posted by: DaveD | 08 June 2016 at 11:56 AM
Actually, I think this is seriously encouraging. They have a genuinely new chemistry Li-S, with a real product targeting a genuinely interesting energy density of 300 Wh/Kg. The ceiling on this technology is much higher than 300 Wh/Kg. This is a real company to watch.
Posted by: msevior | 09 June 2016 at 04:43 PM
These could become near future 2X and 3X batteries if built in the right places?
Posted by: HarveyD | 13 June 2016 at 08:15 AM