Rechargeable Batteries

[[old] canadiancp]

Hi - after 15 months of steady use on our new Concept 2, the batteries finally died. <br /><br />We replaced them with "regular" batteries - our questions:<br /><br />1. What are the best type of batteries to use? Do they need to be alkaline as was in the machine originally (or does it matter)? <br />2. Does it make sense to use rechargeable batteries? <br /><br /><br />We love our Concept 2 (and the forums) - I've been to take up outdoor rowing (summers only as I'm a Canadian weather-wimp), and my husband is busily virtually rowing to the North Pole. <br /><br />Cheers!!! <br /><br />

[[old] Terry S]

Seems to me that with 15 months battery life, you're wasting your time with rechargeables. Change them every year and you should be fine.<br /><br />Terry

[[old] c2scott]

Alkaline batteries are best. Rechargable batteries loose about 10% per month just sitting on the shelf. If you wish to use rechargables, we've successfully used NiMH batteries. I do not recommend Lion batteries as they have a different voltage.<br /><br />When you are rowing, the Model D supplies almost all the power the PM3 needs. The PM3 will NOT charge rechargable batteries.

[[old] rspenger]

<!--quoteo(post=58286:date=Mar 3 2006, 07:41 AM:name=c2scott)--><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><div class='genmed'><b>QUOTE(c2scott @ Mar 3 2006, 07:41 AM) </b></div></td></tr><tr><td class='quote'>Alkaline batteries are best. Rechargable batteries loose about 10% per month just sitting on the shelf. If you wish to use rechargables, we've successfully used NiMH batteries. I do not recommend Lion batteries as they have a different voltage.<br /> </td></tr></table><br /><br />Scott,<br /><br />The Lion cells (sorry, I just can't bring myself to use the word battery for a single unit) obviously have a drastically different voltage, but the NiMH (and NiCads) are significally different afrom the alkalines (and the old Zn/NH4Cl/MnO2), i.e. 1.2V vs 1.5V. I am often surprised that they are treated as if they were equivalent. I remember hearing of a couple of devices that would not function properly with only 80% of the voltage of the alkaline cells. Any comment?<br /><br />regards,<br /><br />Bob S.

[[old] c2scott]

We've used the NiMH batteries in the past. In fact, when we were using WiFi for racing, the Alkalines just could not handle the high continuous demand: Alkalines should give (no generator) 350 hours with no WiFi, and probably 35 hours (guess) with WiFi based on energy density. However, the Alkalines need a "Rest", they don't like a high continous draw. In a race situation, they'd last all of 4 hours! So, NiMH's can handle this high demand very well, and we can get 16-20 hours from them! But, WiFi has been discontinued. Anyone want to buy some used NiMH's? Bottom line though is the PM3 can go WAY down in voltage. But, I'd have to do some schematic analisys to determine if the higher voltages of the LiON batteries would smoke something or not...<br /><br />All this I suppose is too much info. Short answer: NiMH = OK, proven. You'll never get a 100% battery level though (they'll start off at about 60-65% which is OK).<br /><br />-- Scott

[[old] brianric]

I have a charger that will bring them up to 100% charge. Takes about 36 to 48 hours to charge them.<br /><!--quoteo(post=58367:date=Mar 3 2006, 07:13 PM:name=c2scott)--><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><div class='genmed'><b>QUOTE(c2scott @ Mar 3 2006, 07:13 PM) </b></div></td></tr><tr><td class='quote'>We've used the NiMH batteries in the past. In fact, when we were using WiFi for racing, the Alkalines just could not handle the high continuous demand: Alkalines should give (no generator) 350 hours with no WiFi, and probably 35 hours (guess) with WiFi based on energy density. However, the Alkalines need a "Rest", they don't like a high continous draw. In a race situation, they'd last all of 4 hours! So, NiMH's can handle this high demand very well, and we can get 16-20 hours from them! But, WiFi has been discontinued. Anyone want to buy some used NiMH's? Bottom line though is the PM3 can go WAY down in voltage. But, I'd have to do some schematic analisys to determine if the higher voltages of the LiON batteries would smoke something or not...<br /><br />All this I suppose is too much info. Short answer: NiMH = OK, proven. You'll never get a 100% battery level though (they'll start off at about 60-65% which is OK).<br /><br />-- Scott<br /> </td></tr></table><br />

[[old] whp4]

<!--quoteo(post=58716:date=Mar 7 2006, 02:42 PM:name=brianric)--><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><div class='genmed'><b>QUOTE(brianric @ Mar 7 2006, 02:42 PM) </b></div></td></tr><tr><td class='quote'>I have a charger that will bring them up to 100% charge. Takes about 36 to 48 hours to charge them.<br /><!--quoteo(post=58367:date=Mar 3 2006, 07:13 PM:name=c2scott)--><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><div class='genmed'><b>QUOTE(c2scott @ Mar 3 2006, 07:13 PM) </b></div></td></tr><tr><td class='quote'>We've used the NiMH batteries in the past. In fact, when we were using WiFi for racing, the Alkalines just could not handle the high continuous demand: Alkalines should give (no generator) 350 hours with no WiFi, and probably 35 hours (guess) with WiFi based on energy density. However, the Alkalines need a "Rest", they don't like a high continous draw. In a race situation, they'd last all of 4 hours! So, NiMH's can handle this high demand very well, and we can get 16-20 hours from them! But, WiFi has been discontinued. Anyone want to buy some used NiMH's? Bottom line though is the PM3 can go WAY down in voltage. But, I'd have to do some schematic analisys to determine if the higher voltages of the LiON batteries would smoke something or not...<br /><br />All this I suppose is too much info. Short answer: NiMH = OK, proven. You'll never get a 100% battery level though (they'll start off at about 60-65% which is OK).<br /><br />-- Scott<br /> </td></tr></table><br /> </td></tr></table><br /><br />Brian, I think Scott is saying that with the rated 1.2V output of NiMH cells, you're going to get a 60-65% reading on the battery level indicator on the PM3. I'd be very interested to see this charger that makes a NiMH cell develop more than 1.35V - it'd probably look pretty spiffy on the shelf next to my cold fusion reactor