Thursday, February 28, 2019

The 7 Pitfalls of Buying Lithium Batteries that We Have Overcome



Experience has helped me learn the pitfalls of buying Lithium Batteries. More importantly, I’m able to avoid these problems and get batteries to the customer at a good price in a reasonable timeframe. There’s no substitute for visiting the actual factory where the cells are made to know who to trust and who to be wary of. I always look for a manufacturer with an experienced track record when looking for new battery suppliers. I seek to establish trust with each and every battery company I work with. Without further ado let’s get to the 7 Pitfalls:


Please read before you commit to a purchase.
Lithium is a rare earth metal that is only found in a few countries in the world.  The largest concentration is in Bolivia.  However, years ago the President of Bolivia made an agreement with the President of Iran, not a friendly country to most of the free non-Muslim world, to sell all of Bolivia’s lithium to Iran.  The next biggest commercial deposits come from China.  Thus, if you want to purchase anything with lithium in it you will probably have to deal with the Chinese.  That is not necessarily a bad thing.  I have discovered that there are many good Chinese capitalistic companies that are anxious to sell their products in the free world.  However, there are some lithium companies in China that are owned by the Chinese Government and have been formed for two purposes: To make money and to give people work.  People who work for these Government entities are like civil servants.  They know that it is difficult to fire them so, in my opinion; it is human nature that they will not pay as close attention to things as a company whose existence depends on keeping the customers happy.

My Experience with Shoddy Battery Factories
About 10 years ago I read an article written by a man from the USA who was in China on a business trip that was unrelated to batteries. He had been contemplating buying a lithium battery pack and had been corresponding to several candidates that proposed to sell him the batteries that he needed. Since he had some spare time he decided to visit some of these factories who had sent him glossy descriptions of their abilities to supply him their batteries. What he discovered on these visits was shocking. He said that some companies were manufacturing batteries in small facilities no bigger than garages while squatting on the floor with only basic tools.   There was no quality control testing.  Fortunately most of the industry has made great progress since those early days.
When I went into the lithium battery business in 2008, and in spite of this advance warning, I felt that I could determine who was a legitimate supplier and who were fraudulent or made poor quality cells.  It turned out that even with my best efforts to evaluate the Chinese lithium battery suppliers I still had some experiences that cost our company a loss in reputation and a large amount of money.  Finally I decided that the only way I could really evaluate some of the companies that made us some good offers was to go to China and do plant surveys.  It was an eye opening experience.  As a result I now routinely go to China to try to stay abreast of the latest technology and most advanced manufacturing techniques.  I try to visit up to 5 factories on each trip.   These China trips have paid off because we now know about many companies that might have caused us pain.  There are literally hundreds of companies who make lithium batteries.  Eventually the market cannot support them all and there will be a winnowing out of their ranks and only the efficient will succeed.  As they struggle and in their desperate effort to survive they are tempted to lower the purity of the chemicals in their cells and take other shortcuts in an effort to lower prices and stay competitive.

Lithium Battery Chemistries – Why We Prefer LiFePO4 Cells
There are a number of different chemistries available in a lithium battery.  These chemistries were created to address specific needs for a particular application.  There is lithium cobalt, which happens to have a high energy density but can be unstable and might spontaneously combust into flames under certain conditions.  The lithium manganese chemistry is more stable but not completely out of the woods as far as spontaneous combustion.  In most countries including the United States both of these chemistries are considered to be hazardous materials and by International Law have to be shipped and disposed of in a proscribed fashion.  Lithium Iron Phosphate is considered to be non-hazardous and is very stable.  Because of its stability the LiFePO4, (lithium Iron Phosphate) chemistry is the one most people including myself prefer.

The 7 Pitfalls of Buying Lithium Batteries:
    1. Poor Quality

    2. Financial Exposure

    3. Unforeseen Costs

    4. Delayed Delivery

    5. Shipping Issues

    6. Labeling and Paperwork Mistakes

    7. Warranty Replacements

1. Poor Quality:
Lithium is a precious and rare metal which is difficult to refine.  There are many different grades of refined lithium available to the battery manufacturer.  Often, in order to become more competitive and lower costs, the manufacturer will buy a lesser purity lithium in order to be more competitive.  Raw Low grade lithium can be as much as 220% lower in cost than high grade refined lithium.  Naturally the finished battery quality will be reflected in the purity of the lithium that is the most active component.  A lower quality lithium battery will not perform as well and will heat up more than the higher purity cell resulting in a shorter battery life.
The internals of a Prismatic lithium battery contain a large number of plates which are stacked one on top of another.   Larger prismatic battery sizes often encounter a problem that is often overlooked by the buyer because of the convenience of interconnecting the cells and the fact that they normally cost less than packs made up of pouch cells or a large quantity of cylindrical cells stacked together.   The difficulty lies in the fact that the innermost plates in a prismatic battery have a difficult time dissipating the heat that is generated when the cell is operating under a heavy load.  Very often this problem can be averted by using a large quantity of smaller thin pouch cells that have no insulating case around each cell.   These thin un-insulated pouch cells and cylindrical cells in a pack exhibit a characteristic of being able to dissipate the heat much faster.  Thus the cylindrical cells and the pouch cells usually have a higher C rating than prismatic batteries.  Pouch and cylindrical packs have a great deal of flexibility to meet physical dimensions and are usually a little lighter in weight than the equivalent prismatic cell.  The factories will generally assemble these packs to their customer’s electrical and physical parameters for no extra charge.  

2. Financial Exposure:
Whenever a person sends money into a foreign country to purchase a product made in that country they become exposed to all sorts of difficulties that have nothing to do with the end product itself.   Things like language barriers, foreign standards, dealing with foreign freight companies, and a myriad of other things can make the transaction have a less than satisfactory outcome.  This especially applies to purchasing expensive lithium batteries or battery packs.  Resolving some of these often unexpected issues can be financially painful and can delay the transaction.

3. Unforeseen Costs:
The cost of a lithium ion battery is usually the primary consideration for many buyers.  This factor is often a trap that the unwary fall into because they do not know that the first cost is often not the total cost.  Shipping transportation costs are often left off the bid price and left to the buyer to figure out.  The simple fact is this.  You will probably get what you pay for.   Since lithium costs are so high the battery longevity must be taken into consideration.  This is not easy to determine without an experienced track record for the manufacturer.

4. Delayed Delivery:
From experience I have concluded that lying is a perfected art form and a way of survival in China.  Except for pricing most Chinese will tell you what you want to hear …. Which is often far from the facts.  Over the years our company has developed contacts with individuals in China who have high ethical standards and will not lie to us.

5. Shipping Issues:
Getting the rechargeable lithium batteries from the factory to your doorstep can be a vexing problem.  Air Freight is the fastest and easiest but also the most expensive.  Traditionally we figure the air shipping costs will be about $3.50 to $4.00 a pound for batteries shipped into a North American International airport on most small shipments of up to 500 pounds.   Air shipments by FedEx, UPS or DHL usually occur with a minimum of difficulty.  Air transit time is generally less than five days.  On all shipments into North America our company typically will bid our battery cells delivered to your doorstep so that the customer does not have to deal with any shipping costs or other unknowns.

Conversely ocean shipping is much cheaper but many times more complicated.  Shipping in 20’ or 40’ containers may be simple by comparison.  Smaller shipments almost become a nuisance to shipping companies that will transfer over 500 container loads in one boat load.  Getting the shipments from the factory dock to the shipping dock and then safely stowed onboard the ship can be froth with problems.  Dock workers openly accept bribes.  Ocean transit time is generally ten to twelve days.  Getting the cargo off the ship and through United States Customs is problematic.  Every document has to be letter perfect and exactly match the label on the boxes.  This is often difficult to do with a Chinese shipping clerk who does not read, understand or write English.  There are seven hurdles that need to be cleared in the process of getting the products to the customer’s doorstep when shipping by boat.  Ocean shipping traditionally will take about 4 to 6 weeks from the time the products leave the factory’s dock.

6. Labeling and Paperwork Mistakes:
All too often a well-meaning Chinese person who does not understand English will label the box, packing slip or commercial invoice incorrectly leaving the shipment languishing in a warehouse and gathering storage charges while the miscommunication paperwork is worked out.  At times the person who sorts the different shipments that came in on the same boat will misdirect a package to the wrong customer causing confusion, delays and additional shipping costs.

7. Warranty Replacements:
Again, The Chinese companies will tell you what you want to hear.  Usually the warranty period is two years on LiFePO4 batteries.  Some of these warrantees are similar to a lead acid battery which is prorated.  If the battery fails the factory will only give you back a portion of your money.  My experience is that most Chinese companies do not send money back easily.  They will not just accept the customer’s word that his battery failed or is weak.  Before they pay off they insist that electrical measurements be taken of the battery and/or pictures to prove that the battery failed.  Even then getting a refund is like pulling teeth.  Many manufacturers will insist that an accepted BMS system be installed on the battery and proof must be shown that you have not overcharged and over-discharged the batteries.  Our company only deals with Chinese manufacturers who give a full replacement on any battery that fails within the two year period.   I have heard some real horror stories about some Chinese factories, which we do not sell, giving their customers a terrible run around until the customer eventually gives up and finally drops the whole matter and never collects the refund amount that they rightfully deserve.

The Electric Car Parts Company does its level best to help our customers avoid all of these pitfalls!

Monday, February 11, 2019

Lithium Battery Packs - 48V 16S LiFePO4 Cells

48V LiFePO4 Lithium Battery Complete Packs
With 200A (350A Peak) BMS


We are pleased to have new 48 Volt Lithium Battery Pack Systems from Bright Star available. Every pack comes with a 200 Amp Continuous and 350 Amp Peak Battery Management System (BMS). The Battery Storage Systems also come with Balancers, Busbars, and Endcaps all put together in a steel box.

The batteries used in the LiFePO4 Battery Packs are the Bright Star 150Ah LiFePO4 Lithium Batteries. The 48V Packs contain either 15 or 16 (15S or 16S) 3.2V 150Ah Batteries connected in series to get 48 volts or 51.2 volts respectively. The 15S packs are used mostly for Battery Energy Storage Systems and the 16S packs can be used for Electric Vehicles (EVs), Golf Carts, Fork Lifts, and other vehicles. The battery cells contained in the Lithium Pack are UL Approved with over 3,000 charge cycles. They are one of our special long-life batteries that are encased in Aluminum to better eliminate heat.

We’ve had many satisfied customers with the Bright Star Batteries and it will be exciting to see what will happen now that they are put together in a complete pack with a BMS and all the other components! Battery Storage technology is advancing at a rapid pace and we are thrilled to have the latest complete Energy Storage Systems with Lithium Batteries!



Specifications for 48V 150Ah 16S LiFePo4 Lithium Battery Pack:

BMS CONTINUOUS CURRENT
200 Amp
BMS PEAK CURRENT
350 Amp
BATTERY POWER
7680 Watts
NUMBER OF LIFEPO4 CELLS
16
TYPICAL CAPACITY
150Ah
NOMINAL VOLTAGE
51.2V
MAX CHARGE VOLTAGE
58.4V
CUT-OFF DISCHARGE VOLTAGE
38.4V
CYCLE LIFE AT STANDARD (80%)
>3000
INTERNAL IMPEDANCE IN MILLIOHMS
<.4
PACK DIMENSIONS
21.6” * 16.1” * 10.1” High
(550 * 410 * 256.5 mm)
PACK WEIGHT
139 Lbs. (63 Kg)
CHARGE WORKING TEMP
32F~+113F (0C~+45C)
DISCHARGE WORKING TEMP F (C)
-4F~+131F (-20C~+55C)
STORAGE TEMP F (C)
-4F~+104F (-20C~+40C)


Pricing Options

Quantity
Price From Factory in China*
1
$3,680
2-5
$3,630
6-11
$3,610
12+
Call for price