Batteries and New Battery Technologies

Nothing more than what is on their web site. They do not nominate an Australian agent and only phone numbers in China. I am not at the stage of phoning up for information yet.

Point is the Fullriver are a common VRLA supplier and it seems they are now offering lithium. I expect it will be their main product line in a short time.

My approach will definitely be lithium but it is still a while away. My little battery gives me 1kW, which is ample to play with for my testing.

My next step will be to determine the battery capacity based on the required power. I will not be making the initial outlay on the full energy requirement.

If your peak demand is for say 8kW then you could start with battery that gives this power. You would only need something like 40Ah lithium to do full power trials. Maybe a bit more if you want to charge at full rate. It would just mean running the diesel more often than if you had larger capacity.

As I said keep an eye on what is happening with lithium and leave the decision as late as you can. Maybe chase up with a few suppliers keen to get their product in the market place.

In any powering application for a yacht it is the power density that counts so you can get out of a tight spot when needed. The lithium will be about 20% of the weight of a VRLA having comparable power output.

China is producing about 20M electric scooters a year so they have a huge market to develop for. People get excited when they can get a new battery that doubles the range and acceleration simply by upgrading to lithium. You can bet every manufacturer has experts in every aspect of the battery development and manufacture putting in 14 hour days to make sure they are up with the competition.

Rick W

 

the only thing i said was that Li-batteries needs controller for charging and discharging...
and if you say that this is not the case with your torch only because the adapter is just a simple cable than this is misleading... suddenly your torch has everything incorporated...
so what?
did i say anything different?

 

I fully agree with you Rick, you converted me also with looking at LiFePRO4
I noticed some nice 10Ah 3.6 LiFePRO4 in a round 37 mm casing. I have to check whether they fit into the "pipe" casing. If so, that is the way to go. I will then place between each battery a double sided through hole pcb with a thin wire coming out to the BMS. But For $1000 I can certainly make one myself. There is enough support on MicroChip to go that route. I estimate I will save $800


I noticed something on the photo's. The 10Ah has a screw type of + and minus. Does that mean one can screw them together into each other to make a long string? If so, that would reduce the potential bad contacts to a lot less in the "pipe" system. By using LiFePO4 it has reduced the numbers already by 3.
Bert

 

Hi Masalai,
Just to wet your appetite. Look at the 300Ampere 24 Volt LiFePO4 pack. The minmimum ordering quantity is 2 !!!! ( your 48 Volt) it will suit you

http://cens.en.alibaba.com/productshowimg/220302374-200581645/300AH_LiFePO4_battery_for_UPS.html

The specs are excellent for your application. But I don't know whether your boat will roll over, when you receive the price for them !!! I dare did not ask for the price. But if I were you, I should just find out. (Please let me know)

Bert

 

Just looking (If you gotta ask, you cannot afford)

 

Bert,
did you have a chance to go through this, I found this pics that show how Sanyo puts together 240 cells.
Also it seems quite cheap (in the USA) to buy fully functional pack from wreckers from USD300 to 500.

 

Very much true.

But we need to know the price to have ourselves double insured for future backtrouble (75 kilogram per batterypack !!!) What a pity, max 300 Ampere charging at 48 Volt, i.e. your genset would do it at 120 Ampere without sweat. If you only discharge the batteries at 40% , not deep dis-charging, your battery would last a lifetime.

What we have to watch out for. A Li-ion battery needs first heavy constant current and then it will switch over to voltage charging/monitoring. i.e. your 1 hour would have to be exceeded. You would probably need 2 hours. I will buy you some earmuffens, or you buy yourself an MP3 with Mozart not to hear the noise from your genset.

 

Whooow, that is a bargain. It is a pity that I live 12000km away from you. I would definitely have bought it at that price. Even if a few B's may have been damaged or bad. This may be a solution for Masalai. Australia from California is not that far for airfreight cost. And if it is second hand, probably no Value Added Tax applicable, maybe import duty.

One needs some electronic background to make the changes to the BMS for a different output voltage or just get a motor for that probably higher voltage.

Bert

 

Kontakt 390

Hi there,

I have some good news for myself. Remember , experiment no 6 on page 34??. I brought the batteries in, they have been exposed to fog, salt, it has rained, but the batteries did not get wet. After 8 days, I popped the batteries into the pipe, connected the motor and had straight away the full power on the motor.

I am going to leave them out for another few days, add another string of batteries and will load them with 3 or 4 Ampere ( I will exceed the NiMH specification, but need to know what happens at higher currents)


That "Kontakt 390" seem to be a nice solution.

Bert

 

battery prices

If you have any hybrid cars in SA you might be able to find similar prices at wrecking yards there? I think this represents the best deals on larger battery sizes, but will soon disappear when everyone catches on, and bids the price up. Some of these packs can be broken up into tubes like you are considering, and that would make them easier to handle.

Lithium cells will probably not be available in wrecker yards for quite awhile, as there almost nothing beyond the prototype vehicles to get into wrecks yet

I don't think prices of Li batteries will drop much with mass production for many years. The demand will remain high and even increase greatly if the world economic recovery takes hold. The prices of raw materials required will increase since significant recycling plants that might help dampen material prices are years away. Already the battery pack that I posted about, and bought several months ago for $48 has been bid up to $89: http://www.amazon.com/gp/product/B000JTBPF6 I think it will easily double in price in the next year.

I think IF we see Li battery prices in a sustained gradual or precipitous drop it will be a bad indication. Either Li will have flopped in applications involving automobiles or a new technology will come into play which is even better. A third possibility is resumption of a world recession where deflation will have come into play. Meanwhile the prices of spiral wound AGMs and high quality Prius nimh will drop, as those industries fight to keep market share.

Porta

 

Sadly, there are probably 5 or 6 hybrid cars in South Africa. Only next year Toyota will start promoting them here.

That would be very sad for us

There is maybe another reason, if the oilindustry will buy the shares up in those mines and pushes the prices out of our boundries. Like they did when they pushed us out of the chair at the RSA solar energy society. I had the plans on the table for the cheapest and the best Silicon solarcells with the best quality silicon sand here in RSA. Electricity was only Rand 0.06 (USA$ 0.009 per KWh at those days. Thus growing silicon was inexpensive. We have alumunium in the ground and hardened unbreakable glass with those electricity prices was also not a problem. (glass on which one could walk and dance) Pity.

Bert

 

parallel batteries

Good advice CDK. I would only add that fuses need to be added between parallel packs and accurate tagging be used to keep the configuration straight for the packs. Fuses are used to prevent discharging of other parallel packs into a battery pack with a bad cell, the most common battery failure mode. Tagging helps if you are in a hurry to replace a battery, or if someone else, not familiar with the configuration has to attempt a repair. Seems like I remember reading that up to 4 cells can be paralleled with Li, maybe not as many with other types.

Porta

 

STAIR- the next battery?

To follow up on my last post, my bets are still on lithium:

http://www.greencarcongress.com/2009/05/stair-20090518.html

As they point out, being able to use atmospheric oxygen cuts weight tremendously. Some others that contenders would be zinc-oxygen, aluminum-oxygen, but these would probably be safer though heavier IF they could be developed as rechargables.

Porta

 

What I ment, is that you can get a 6.5kw brushless of 1.5kg for 150usd, 6.2k noload RPM.
ESC about the same price - monster 2000 or possibly the marine.
These are turnigy parts from hobbycity. Some bad rep for magnets coming loose and general qc issues - nothing really serious IMO.

Formerly there was only plettenberg (>10kw motors for 1000$), torcman monster 4.5kw (torqeedo motor) for 4-500$ or industrial heavy expensive motors - unless you wanted >10k rpm.

Now, these are RC ratings - means that a significant airflow is probably assumed.
The torqeedo is using passive watercooling externally to the stator carrier.

Given that bearings are the only wear parts in BLDC (possibly magnets too?), I think the price difference from turnigy to the top quality motors are too big to justify for me.

100A charging, I think you have got the good idea - using a commercial charger and balancer in parallell to a home made brute, being shut off at 90% some how. 100A/50v worth of FET/IGBTshould not be that expensive.
You may get away with a constant current, and shut it down on overvoltage, or you could do cc/cv and shut down on low current, this might result in faster charging. Using 2x 6s chargers in place of the shculze unit would save some $.

Something else just came to mind; due to charge termination triggered by low current on most common li chargers (I guess), they could be unsuited for solar and other low/variable current sources. Just something that might need to be thought about. Texas instruments has a small charger chip (bq something) suited for current limited apps too, not sure what the charge termination is based on in those. Could be just overvoltage trips a timer.

 

Vic
I am inclined to disagree with this. When you consider the size of the Chinese market the rest of the world is miniscule. We should be able to feed off their droppings at marginal cost. It will be a long time before China has the same cost structure. Their economy is considerably more efficient than modern western economies. Most of what they build is greenfield and not tethered to aged infrastructure. I expect the majority of the motorised population are already using electric vehicles.

The price fluctuations depend more on the currency you are using. Offshore products I look at in AUD are still getting cheaper.

Lithium is still in the rapidly developing phase so there will be better offerings coming for many years yet. This means rapid obsolescence so manufacturers will be forced to move product that is at risk of being outdated. This has occurred with computers, tubed TVs, now with flat panel TVs, zinc/carbon primary batteries, ni/cd rechargeable batteries and no doubt many other items. It may be that VRLA batteries are giveaways in 2 years time - could make nice door stops.

Rick W