Re: [Elecraft] Alternative battery for K2?
The charging scheme for the K2 internal battery is based on using an SLA battery. If the battery is changed to another battery chemistry, the charging circuit would have to be modified to match the charging requirements of the replacement battery type. Since Lithium batteries require very special charging techniques, this is a matter that is not to be taken lightly. A simple replacement of the K2 SLA battery with another battery chemistry would have to be a redesign of the charging mechanism. 73, Don W3FPR On 8/15/2015 11:33 PM, TF3KX wrote: Hi everyone. Has anyone any experience or suggestions on replacing an aging internal K2 battery (the standard lead-acid type) with one of the newer, lighter and more energy-dense batteries? I know there were some safety concerns with lithium-based batteries early on, but now that they are are used in all sorts of electronic gadgets, wouldn't there be some that would have the right form factor and voltage to fit in for the existing K2 battery? -- View this message in context: http://elecraft.365791.n2.nabble.com/Alternative-battery-for-K2-tp7606331.html Sent from the Elecraft mailing list archive at Nabble.com. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to w3...@embarqmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Alternative battery for K2?
I use a 4-cell LiFePO4 battery, with Anderson Power Pole pigtail, connected externally to the K2. Easy to change batteries without having to open the rig, and by recharging the battery external to the radio there is no risk of engulfing my beloved K2 in a spectacular ball of flame. -- 73 de Matt VK2RQ Le 16 août 2015 à 1:33:44 PM, TF3KX (kristi...@gmail.com) a écrit: Hi everyone. Has anyone any experience or suggestions on replacing an aging internal K2 battery (the standard lead-acid type) with one of the newer, lighter and more energy-dense batteries? I know there were some safety concerns with lithium-based batteries early on, but now that they are are used in all sorts of electronic gadgets, wouldn't there be some that would have the right form factor and voltage to fit in for the existing K2 battery? -- View this message in context: http://elecraft.365791.n2.nabble.com/Alternative-battery-for-K2-tp7606331.html Sent from the Elecraft mailing list archive at Nabble.com. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to matt.vk...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Alternative battery for K2?
Don Wilhelm writes: > The charging scheme for the K2 internal battery is based on using an > SLA battery. If the battery is changed to another battery chemistry, > the charging circuit would have to be modified to match the charging > requirements of the replacement battery type. > Since Lithium batteries require very special charging techniques, this > is a matter that is not to be taken lightly. > A simple replacement of the K2 SLA battery with another battery > chemistry would have to be a redesign of the charging mechanism. Don is of course right about simply putting in a battery with different chemistry. But, there are LiFePO4 batteries with integrated controllers specifically made so that they can be substituted for lead acid in existing equipment. Basically it has a charge controller for the LiFePO4 that operates on the charging voltage for lead acid. This item replaces the 7Ah size; I don't know if there's an equivalent item for the size in the K2. http://www.amazon.com/A123-Systems-ALM-12V7/dp/B008VVO6LE/ref=pd_sim_sbs_328_12?ie=UTF8&refRID=0R6H1NBH31JQ509VCJ3V (I have not tried this; I'm still a lead-acid using dinosaur.) 73 de n1dam __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Alternative battery for K2?
I soon (12-13 years ago) decided I didn't want a battery inside the K2 -- so it was removed and only external batteries used. I was overly(?) concerned about leakage and such issues. I'd have the same, or greater, concerns with some of the newer, higher-density batteries if inside my K2. 73, Phil W7OX On 8/15/15 8:33 PM, TF3KX wrote: Hi everyone. Has anyone any experience or suggestions on replacing an aging internal K2 battery (the standard lead-acid type) with one of the newer, lighter and more energy-dense batteries? I know there were some safety concerns with lithium-based batteries early on, but now that they are are used in all sorts of electronic gadgets, wouldn't there be some that would have the right form factor and voltage to fit in for the existing K2 battery? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Alternative battery for K2?
I had a 4 cell LiFePO4 battery inside my K2 for quite a while. It was about the same size as the original SLA. I found that I was able to charge it with the built-in SLA charging circuit as a matter of routine and the cells remained in balance, as verified by an occasional balance charge with a CellPro Multi4. The reason this worked well was because the cells in the pack were all of good quality, the discharge rate was not excessive, the built-in K2 charger charged at low current, and I was careful not to leave the charging circuit on for prolonged periods. LiFePO4 will tolerate limited low current "overcharging" fairly well and without the danger associated with doing the same with regular Li-Poly chemistry, and in my experience without damaging the cells. Of course, ultimate cell life may be only 500 cycles instead of the 2000 you might expect with good LiFePO4 cells and use of a quality balance charger, but I never found any degradation. I agree with others that have replied, however, that just using an external LiFePO4 pack entails little disadvantage, and that is what I do now myself. Chip __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com