You folks are absolutely correct and I was unclear.<br><br>These batteries are rated to be charged at 1C, which is in the product description. What this means is, the battery must be charged at a rate that is equal to or less than the capacity of the battery, so less than 4 amps.<br>
<br>As a rule of thumb, all LIPO's are usually charged at 1C or less. This means, no matter the capacity, you do not want to charge a LIPO battery at such a rate that an empty battery would be charged in less than an hour.<br>
<br>Sorry about not mentioning that.<br><br>To understand how the circuitry in this battery works, we need to understand how this battery was designed to be used. This battery is meant to be a drop in replacement for a transmitter battery. The transmitter can recharge the battery when wall power is provided. The transmitter then trickle charges a 6 cell NIMH pack over two leads.<br>
<br>This battery is meant to do exactly that. It is meant to replace a bonehead simple NIMH pack in a transmitter in an off the shelf fashion.<br><br>So, how would one safely use this pack? Trickle charge it at 9V at less than an amp. It will take all night to charge, but it should charge safely.<br>
<div class="gmail_quote">On Wed, Sep 14, 2011 at 1:59 PM, Taylor Alexander <span dir="ltr"><<a href="mailto:tlalexander@gmail.com">tlalexander@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div class="gmail_quote"><div class="im"><div><br></div><div> </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">For all intents and purposes, a 9v DC source should be all that is needed to charge this pack.</blockquote>
<div> </div></div><div>I don't know specifics, but I'm inclined to believe that isn't the case. The protection circuits are only there to prevent overcurrent and over/under voltage conditions. They don't do any charge current regulating and I'm pretty sure LiPo cells want that. At least, I do know that even though all of Sparkfun's single cell battery packs have protection circuits, they always say you need a lipo charge circuit and I've never heard anything about charging a LiPo off straight DC. Given how handy that would be, I'm inclined to believe I would have heard something about that.</div>
<div><br></div><div>So like I said, I don't know anything for sure, but if you don't either, then there's probably more to it. Either way its something you should definitely be sure of before trying.</div><div>
<br></div><div>-Taylor</div><div><br></div><div><br></div><div> </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div><div></div><div class="h5">
As long as you only need to provide 7.4 volts at 8 amps, you should be fine. This pack only has two leads. That's for voltage in and out. No LIPO charging equipment required. My expectation is that there is some circuitry in the pack that does this for you. <br>
<br><div class="gmail_quote">On Wed, Sep 14, 2011 at 11:04 AM, William Garrido <span dir="ltr"><<a href="mailto:blackspartan117@gmail.com" target="_blank">blackspartan117@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
Nice! This would be great to drive my motors. I doubt my charger for LiPo would work, anyone know if a small LiPo charger for 2S? I have my chargers embedded on my robot.<div><br></div><div>Or even my MC, would get rid of the need for a stepup! Too bad its not 6AH. </div>
<div><br></div><div><br><div class="gmail_quote"><div><div></div><div><div><div></div><div>On Wed, Sep 14, 2011 at 10:10 AM, Corey McGuire <span dir="ltr"><<a href="mailto:coreyfro@coreyfro.com" target="_blank">coreyfro@coreyfro.com</a>></span> wrote:<br>
</div></div></div></div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div><div></div><div><div><div></div><div>
Need to replace NICAD/NIMH packs, but are afraid of the complexity of LIPO or added charger cost? This pack might fit your bill.<br><br><a href="http://www.hobbyking.com/hobbyking/store/__19481__Turnigy_4000mAh_Spektrum_DX8_Intelligent_Transmitter_Pack..html" target="_blank">http://www.hobbyking.com/hobbyking/store/__19481__Turnigy_4000mAh_Spektrum_DX8_Intelligent_Transmitter_Pack..html</a><br>
<br>Sparkfun and other places have single cells that have such cutoff circuitry to protect your single cell from being charged too high or discharged too low, but this is the first 2S solution I've seen. 2S LIPO is a sweet spot because it nearly perfectly matches the voltage characteristics of 6 Cell NICAD/NIMH packs, which are common everywhere. This could be a drop in replacement for such needs.<br>
<br>One draw back, it appears to provide only 8 amps of current. This is, no doubt, because the circuit that regulates charge is in line with whatever you plug it in to.<br></div></div></div></div><font color="#888888">
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