Lithium-NMC Technical Data & Info

The batteries that we use on our Golf Skate Caddy are the most advanced and highest quality battery available today; they are the awesome Li-NMC battery. These batteries are regarded as safe and non-combustible as they do not contain any volatile material in construction. These are NOT to be confused with the similar sounding lithium ion (cobalt oxide) LiCoO2 battery found in mobile phones and similar devices. This type of battery does contain material, which may become volatile.

When we designed the concept of the golf skate caddy we felt that we had to meet several important criteria, with reliability heading the list along with safety and ease of use. Understanding battery technology, we felt we were left with no other choice than to use this type of battery.

 

 


In our research some of our competitors produce great but expensive single ride on units, but we feel that these are let down by sub optimal batteries. In some cases there are units that sell for around $4500 - $5000 and have a battery system worth around $300 - $400. This might sound like a lot, however the battery system is the heart and soul of any electric transport vehicle. What happens with these types of vehicle due to their weight (around 350kg fully laden) is that immense stress is placed on these batteries and failure can start as soon as 3 months.

Because of this we opted for the top of line Li-NMC (LiNiMnCoO2) 30AH battery. These batteries have efficiency per weight compared to sealed dry lead batteries of 6 to 1. In other words our 6.5 kg battery has the same power output as a bank of dry cell Lead acid weighing 40+kg. Wow !!!

In a world where electric vehicles are ruled by weight, you can see why we opted for the  Li-NMC batteries.

Li-NMC batteries have a typical discharge / recharge cycle rate at 80% Depth of Discharge* of over 1000 cycles and at 50% Depth of Discharge this can increase again further to 1200-1500 cycles.. The trick to ensuring maximum cycle recharges is to ensure that you have plenty of capacity to start with. Using a battery that only has minimal capacity reserve will take you to the limit and stress your battery out, effectively reducing its serviceable life and in the case of dry cell lead acid batteries this could be months instead of years. In our research some competitors have only been achieving 3 months of battery life using dry cell batteries due to the excessive loads applied to them. This was one of the major directives that we set out to over come when we designed and developed the Golf Skate Caddy.

The NMC cells compromise between high current rate and high capacity rate. The NMC cells provide higher energy density with lower cost,
long cycle life (>1000@1.0C, IEC standrad).
NMC cell has 3.6 +/- 0.5V nominal working voltage and shall be cut-off power at 4.15-4.20V per cell during charging.

The secret of NMC lies in combining nickel and manganese. An analogy of this is table salt, in which the main ingredients of sodium and chloride are toxic on their own but mixing them serves as seasoning salt and food preserver. Nickel is known for its high specific energy but low stability; manganese has the benefit of forming a spinel structure to achieve very low internal resistance but offers a low specific energy. Combining the metals brings out the best in each.

NMC is the battery of choice for power tools and powertrains for vehicles. The cathode combination of one-third nickel, one-third manganese and one-third cobalt offers a unique blend that also lowers raw material cost due to reduced cobalt 

content. Striking the right balance is important and manufacturers keep their recipes a well-guarded secret. Figure 7 demonstrates the characteristics of the NMC.