Hybrid or hybridize

[teoman]

I found some LG 43 Ah cells that are relatively cheap over here and was thinking of buying them and putting them to use. (Same cells as hyundai ioniq)


I can buy something like a CR-Z and put the pack in parallel.

Ideally the altermotor route would be the beat option. But i do not know how to drive the altermotor. I am however capable of using the canbus to calculate a reference for the motor. I.e something like power on low rpm and cutoff at 2000 rpm and recharge when gas pedal not depressed and rpms above 2500 (obviously i am engine braking) or when brake pedal is applied and car is moving.


What is reasonnably possible.

[teoman]

Would the CR-Z start complaining if I constantly charged its battery pack a couple of volts below the max voltage?

Would it provide assist all the time? (Current pack I have is 6.7kwh, but i am thinking of getting 4 more packs like this to get the voltage closer.

[S Keith]

How will you manage/charge the LG battery? LiFePO4 or LiPo?

I don't have exact data, but based on known values for other Honda hybrids, the CR-Z may charge to a maximum of 134V UNDER HEAVY REGENERATIVE BRAKING. You'll want your Lithium pack max voltage to be well above this value.

Continually push a NiMH battery to 100% SoC, and you'll wear it out pretty quickly.

[teoman]

CRZ pack seems to be 101V or so.

I can build a pack to whatecer spec necessary.


For an initial approach I had in mind a boost converter or a buck converter to charge the original pack.

[S Keith]

Nominally, yes, but you will never see a CR-Z pack resting at 101V unless it's completely dead.

[teoman]

I can feed the pack whatever voltage needed.

Will the electronics complain? Will i get constant e-assist? And will this boost fuel economy.

[S Keith]

Probably not. No. A very small amount.

[teoman]

It has a 10kW motor. Could it not be coerced to be active more of the time?

[vskid3]

Originally Posted by teoman

For an initial approach I had in mind a boost converter or a buck converter to charge the original pack.

Look into the Enginer PHEV kits for the Prius, they used a 48v battery and boosted the voltage to the pack voltage.

Modifying the electrical side of most hybrids is difficult and the results usually aren't very impressive. If you already had the batteries and the car sitting around, and a really good idea of how to make them work together, I would say go for it. But in your case, I wouldn't. If you really want to buy the batteries and do something with them, a project like an electric motorcycle or e-bike would be a better use of your time.

[teoman]

I have a 6.7 kW pack now. But I can get more cells.

A new Plus Sport System is standard. If the battery is more than 30 percent charged and the CR-Z is traveling over 18 mph, the driver can press the "S+" button on the steering wheel to deliver increased acceleration for up to five seconds. Manual-transmission versions also receive both a larger clutch and a new lower final drive ratio. EPA-rated fuel economy figures increased by 1 mpg city for CVT equipped models, and 1 mpg highway for those with the six-speed manual transmission

Would constantly pressing this boost button work?