A mate and me are looking at getting a group buy together for 40ah LTO cells from china. I am wondering if anyone would be interested in getting some. Specs: Model OSN-LTO-66160H Materials LTO Nominal capacity 40Ah Nominal voltage 2.3 V Dimension Length: 160±1.5mm Diameter: 66±1mm Weight 1.24±0.1kg Internal Resistance ≤1mΩ Operating voltage Charge cut-off voltage 2.8 V Discharge cut-off voltage 1.5 V Standard charge/discharge current Charge current 1C(40 A) Discharge current 1C(40A) Maximum charge current 10C Maximum discharge current 10C Cycle life 30000 times Operating Thermal Ambient Charging -50℃~ 65℃ Discharging -50℃~ 65℃ Storage Thermal Ambient Short term(within 1 month) -20℃~ 45℃ 36usd EACH - BEFORE shipping, shipping will obviously depend on the number we order. The more we order, the cheaper it will get both in volume discount and shipping , if we can get a indicative number we can get a quote. 6 of these will match a lead acid battery of around 80ah capacity, but be 1/3 the weight, and have a massively longer life time. Pros: Massive current capacity and lifetime compared to lithiums. Cons: Lower full cell voltage which means you need more of them to get the voltage you need. However - lead acid management systems will work with these as 6 cells in series are a perfect replacement for a SLA/Flooded battery. We are initially getting 24 in for testing and experimentation in the next month or two, we will be creating a pack for a ute based power pack to replace SLA. We will also be using that time to look at what balancing systems are required. If needed we might look at the systems that supercap banks use for charge equalisation. More info on LTO: The Lithium Titanate (LTO) battery This technology is known for its very fast charging, low internal resistance/high charge and discharge-rate, very high cycle life, and excellent endurance/safety. It has found use mostly in electric vehicles and energy storage (Toshiba, YABO, and Altair Nanotechnologies), and wristwatches (Seiko). More recently, it is beginning to find use in mobile medical devices due to its high safety. One underlying reason for this technology's characteristics is that the chemistry uses nanocrystals on the anode instead of carbon, which provides much more effective surface area. Unfortunately, however, this battery has lower terminal voltages than other Lithium types. Specific energy: approximately 30-110Wh/kg Energy density: as high as 177 Wh/L Specific power: 3,000-5,100 W/kg (peak load) Discharge efficiency: approximately 85%; charge efficiency over 95% (low-rate) Energy/consumer-price: 0.5 Wh/dollar Service or shelf life: >10 years (some to 20 years) Self-discharge: 2-5 %/month Cycle durability: 6,000 cycles to 90% capacity (some models >10,000 cycles) Nominal cell voltage: 1.9 to 2.4V (Toshiba SCiB cells 1.5-2.7V operating; 2.3V nominal) Cut-off voltage: 1.5V typical (some at 1.7V) Temperature: -40 to +55°C (extended models) Charging technique is using standard constant current, followed by constant voltage until the amps threshold is reached.