Monday, August 19, 2013

A123 Nanophosphate® AMP20M1HD-A cells with compression end panels.

I took the A123 end panels I received a few days ago and stacked 12 A123 20Ah cells between the two ends to see how thick they would end up. The pack will be a 43.8V max pack with 20Ah of capacity. I don't plan on using a BMS and will just monitor the pack with Cell-Logs and use a Hyperion balance charger.

The 12 A123 pouch cells by themselves are just about 4 inches tall. With the end compression panels, the pack is almost 6" tall!

You can see the rounded slots for the tension bands to wrap around the entire package. The recommended compression pressure is quite high so specialized tools will be needed to do the banding.

Here's a ruler against the pack. It's about 5.75" tall. Each end panel is just about 1" thick and each is quite hefty.

I'll do more measurements of the dimensions and weight later.


Sunday, August 18, 2013

E+ (EMS) motor and battery disassembly

I had a very generous E+ electric bike owner send me his non-functioning motor and battery to test and do a post-mortem.

I received it a couple of weeks ago but I finally bought a 3-jaw puller and was able to open both of them up. Here are some photos and observations.

Here's the 3-jaw puller about to open the motor.

The rusty battery ring. There is a powdery material lining the inside of the casing which is quite curious. At first, I thought it was salt but the motor is from Austin which doesn't use salt on the roads since it doesn't snow there often.

The very rusty coils of the E+ motor. Interestingly, seeing the inside of the motor confirms that the motor is a 3 phase motor. The Tidalforce motors have 7 phases.

Better photo of the rusty coils. Rust alone would not stop the motor from working but it probably would be good to stop it or at least slow it down. Perhaps a slight clean up and conformal coating is in order.

Close-up of the 3 hall sensors placed between the coils and on a circuit board.

In order to open the battery hub, you'll need a snap ring tool or very good needle nose plier skills.

First impressions. This is a beautifully made battery. The tabs are welded very cleanly and the circuit board and cast casing are beautifully made. This looks brand new compared to the motor!

The axle casting and frame to hold the batteries are really high quality.

Again, the circuit board (BMS) and wiring are truly first rate.

The battery segments are joined by heavy heat-shrink wiring that is bolted in place. There are other segments joined by welded tabs.

The cells are not the SAFT French NiMH cells but are slightly higher capacity 10000 mAh Chinese made cells.

The 30 D sized NiMH cells are arranged into 6 5 identical cell groups for easier replacement.

The battery and motor side-by-side.

More later,

Saturday, August 17, 2013

Tidalforce iO Stepthrough

I'm now working on a Tidalforce iO Stepthrough. It's a bit rough and scratched up and in need of some TLC. The fork is in relatively good shape. I have a 9 Continents motor in it right now but will probably put a Tidalforce Wavecrest motor and console on for authenticity's sake. I will need to install a third party battery and a front wheel with disc brakes. The coloris gray with green undertones. A very Eco color.

Here's the bike with the 9C. The bike came with the Topeak Explorer rack.

I had a suspension seat post but don't have a clamp.

I installed a new kickstand and pedals.

Designed and assembled in the USA. (In Dulles, Virginia)

No metal iO on the Stepthrough, only a painted one.