GM Inside News Forum - View Single Post - IL Corrects Volt Story: Batteries Will NOT Charge When Driving; GM Website Differs

rcracedriver · 09-23-2008, 10:42 PM

It sounds to me that this method is designed to increase battery life AND fuel economy.

From wikipedia:
Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a long time, they should be brought to a charge level of around 40%–60%. Lithium-ion batteries should not be frequently fully discharged and recharged ("deep-cycled") like Ni-Cd batteries, but this is necessary after about every 30th recharge to recalibrate any external electronic "fuel gauge" (e. g. State Of Charge meter). This prevents the fuel gauge from showing an incorrect battery charge.[20]

So, therefore this method cuts out extra cylcles. My assumption is there's some ultra capacitors on board the volt that the gas engine is constantly topping off to deliver power to the motor after the batteries are drawn down.

Furthermore, if the gas engine were required to recharge the batteries, it would have to be more powerfull and suck more fuel to get it done. That being said, I think the engineers have done the right thing.

09-23-2008, 10:42 PM	#22 (permalink)
rcracedriver 2.4 Liter SIDI ECOTEC Join Date: Aug 2006 Posts: 142	Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving It sounds to me that this method is designed to increase battery life AND fuel economy. From wikipedia: Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a long time, they should be brought to a charge level of around 40%–60%. Lithium-ion batteries should not be frequently fully discharged and recharged ("deep-cycled") like Ni-Cd batteries, but this is necessary after about every 30th recharge to recalibrate any external electronic "fuel gauge" (e. g. State Of Charge meter). This prevents the fuel gauge from showing an incorrect battery charge.[20] So, therefore this method cuts out extra cylcles. My assumption is there's some ultra capacitors on board the volt that the gas engine is constantly topping off to deliver power to the motor after the batteries are drawn down. Furthermore, if the gas engine were required to recharge the batteries, it would have to be more powerfull and suck more fuel to get it done. That being said, I think the engineers have done the right thing.