Recent content by countermeasure

Most impressive Doc. Are those brackets holding the modules together custom made? What size and type of wiring do you use for the interconnect? Do you have a picture showing the interconnection and the AC side of things (show us the stuff under the metal cover)? Thanks.

Out of curiosity, I called the person behind the "authorized dealer" for A123 cells. His name is Erik. This is what we talked about: I asked about the B grade cells and what it means. He told me he just got the B grade cells from Maine. And honestly have no idea what that B grade is. He...

Out of curiosity. What is your procedure to match battery cells of the same chemistry, same AH rating, same manufacturer? Dogman? Dmun? I am also planning on paralleling A123 M1 LifePO4 cells in 4P configuration. And then into 4S packs to make a 12V starting battery substitute for a car. 4P...

The rectangle on the left, with 3 Chinese characters, is the charger. The rectangle on the right, with 2 Chinese characters, is the load. The BA with Chinese characters, is the battery plug BA.

OK. Got my powerlab 6 charger. Power source is 12 V, 14 Amp Pyramid DC power supply used for audio amplifier. Room temp at 65 F. Charge at 8 Amp. Discharge at 2.25 Amp, or 1C. 1S M1A cell discharge. Cell from ES for sell forum. Disassembled from 3S pack. I don't have the balancing wire...

Good suggestion. I went back and studied the charger's manual, in this case the Turnigy Accucell 8150. There is no mention of using the balance wire as part of the 1S test discharge. I figured since it's just one cell, two wires is enough for this particular charger. The M1B was also...

For kicks, here is an M1A discharge test. Same room temp as above. Only got 2208 mAH, not the 2300 mAH nominal. I will verify again when I get a Powerlab 6.

Got a chance to play with the M1B. Room temp is 64 F according to thermostat. Charged up first. And then immediate discharge, result is 2497 mAH. Just want to point out that the Turnigy charger volt meter isn't accurate. Will try more charge-discharge tests once I get a Powerlab 6.

Doc. Very impressive build. A couple questions. 1. What are those blue sheets lining the aluminum case? Foam? Insulation? 2. Are those yellow ring connectors crimping connectors used in the automotive industry? 3. What are those molex connectors on the right hand side of the picture for...

Guys. I just dug through a lawsuit file against A123, on the AMP20 pouch cells. Downloaded the original document from stanford.edu. It's 66 pages long. Here is my take away: 1. The original AMP20 is made in Korea. The Korean cells seemed OK. The US operation was setup later with Korean...

Different M1 cell grades *Only applies to M1A, 2.3 AH Lot number code FHYYMMXXX-G F: Cylinder cell H: Plant YY: Production year MM: Production month XXX: Production day G:Capacity Grade “P” 2400 ≤ tested capacity mAh Grade “R” 2300 ≤ tested capacity < 2400 mAh Grade “T” 2200 ≤ tested...

M1A and M1B specification sheet

Hi guys. I have these A123 26650 M1b cells. I would like to run a cycle test on a single cell. So far I have seen Powerlab 6, CBA IV, and iChargers on the internet. There may be other equipment or makes I don't know about. Objective: Identify long term cycle effect of the cells at 1C, 2C...

Comparing M1A and M1B battery cells. M1B was purchased from batteryspace.com. M1A is from ES for sale forum, disassembled 3s pack with BMS removed. In the pictures, M1B has the trash can symbol. The bar codes are a bit different. The last picture shows two M1B cells. The shrink wrap are...

Cell Level fusing. Tesla.