Friday, January 16, 2009

Batteries arrive

After a very long wait (6-7 weeks) the order of lithium batteries, charger and BMS have finally arrived! I actually ended up picking up the shipment from the freight distribution point closest to me instead of waiting another couple days to schedule the delivery with them.

As I've mentioned before I ordered everything through Elite Power Solutions. You really don't know what to expect when dealing with people online and especially for this kind of money but everything went smoothly and they are legit.

Below is a picture of the crated delivery. Five boxes total. Three boxes contain 15 cells each, one for the charger and another for the BMS system.

Here you can the first box opened. I didn't know what I was going to get really other than lithium cells. They came pre-bound with nice aluminum end plates and handles to carry them. It's very important these cells stay bound while there is any charge on them. So for example if you need to exchange a single cell for some reason the entire block that is bound together must be drained completely first. I didn't know this until reading the instruction manual. I didn't get this with the order but found the info on the Thunder-Sky website.

Here is just a picture of everything received in the order. You can see charger isn't small.

I measured and added the post dimensions for these cells. Again these are the 160Ah cells so I doubt they are the same for other cell sizes but I'm not sure. This info will be helpful if you are making a per cell battery balancing system. The BMS only monitors the and reports information about the cells. The only active BMS piece to it is shutting down the charger when the highest cell reaches a set voltage. I will be charging to 3.8v max. This means the cells can become out of balance which will reduce the overall power you can get from the pack safely.

Here is the best shot I could get showing a side and front angle of the aluminum end caps that came with the cells. You may need to, as I do, use longer or shorter groups of cells than five. I need to find some similar straps that are longer but will reuse the end caps.

Here is a box of all the connector bars, bolts and locking washing to put your cells in series. These also came with the cells. The wires you see there are actually part of the charger. There are two connectors which you must wire into the outlet style you want (one for 120v and one for 240v). I was expecting only 240V so this is nice I will now add two separate plug types on the car so I can recharge anywhere (120V plugs are much more common here). Using 120V will double the time it takes to charge, but it's better than not charging.

Here is the charger. Elite has a variety of options here. I picked the 200V max, 24 amp max charger. You can dial in the voltage and amps you'd like to charge at. This makes this charger very versatile for different pack configurations and charge stations. So if perhaps you are sharing an outlet with some other amp sucking EV you can dial down the amp draw and avoid a tripped breaker. The back, which I forget to show, has a DB9 connector for the BMS interface and the two power connectors.

Here is the BMS. Damn there are a lot of wires and connectors in this box. I'll go into more detail on the pieces here and the others as I install them to show which connections go where. I'm also currently waiting on the English instruction version for the BMS. I don't read Chinese sadly.
That's it for now until I get time to start building the battery racks and get this all installed. Hopefully soon!


Anonymous said...

Hey Brian,

Rob again. I'm envious of the pack but not the price! None the less, I expect I'll be following your path...

I really like the look of the strapping and Al end plates. I'm guessing the plates add about .375 of an inch per plate?

I will need 4 packs 9 cells wide and 4 of 2 to fit my car. I suppose the factory could prepack to this requirement? Were you given that kind of option? I wonder if they will sell those plates separately?

Great progress, very exciting!

Brian said...

Ignore my 110mm terminal width. Looks like my digital caliper is having some issues. Assume the 106mm width that TS is claiming.

The plates change depth but the thickest point is .350".

I wasn't asked how many cells per pack I would like nor the length of the cables for my BMS monitoring. Both would have been nice.

I'm guessing you could order just the plates. I ended up with extra plates after arranging some of my cells into larger packs.