Using Turnigy Lipo 5 Ah Packs To Replace 12v Lead Acid In A Robots

 
#1

This is basic info for getting novice and experience builders good info on lipo. If your a new builder don't use lipo unless your remove the pack and.charge it separately.

Turnigy is a great international battery brand and shows up cheap on hobbyking often. One of these 5ah packs has 3/4 capacity of a 7ah lead acid but weight 1/3 as much and 1/3 the physical size. At the time of this post I could get this pack for 21 dollars from hobby.king.
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These weight 412 grams, that's about .94 pounds per lipo battery. 5 would be give pounds. Crazy.light.huh?

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This is a tray of 4 5ah lipo in a battery tray. , that's 20ahah of power , in my robot I could.have two trays with 40 ah and still only weight 10 pounds. Take in mind a 12v 7ah lead acid is 6 pounds. 4 of them is 24. That's half the weight and more capacity!

Loop can be.charged two ways. A balance.charger to get the max out of the pack or direct charge. The input voltage must be exact however. A tray of 4 batteries.charged to max looks like this...
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You can pick up a charger that does 4 to 8 packs at once however.

3s pack is 11.1v at it's lowest point, that's considered dead at 3.7v per cell. Full charge is 4.2 v per cell.
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Full charge a 3s battery pack is 12.8 volts.... A great replacement for lead acid.batteries

#2

This 4 port charger is excellent. The one directly above. It charges each battery individually and monitors charge rate. This provides safe and fast charging. This charger takes up to 16v in DC. So if this was installed inside your not, one 12v to 16 volt input could charge all your loop batteries safely and quickly. Obviously 8 batteries would require two charger units.

#3

Thanks Josh! I think I will go that route instead. It works in my case because my bot wont self charge.

#4

Sweet man , 4 of these packs is 84 dollars , 2 is 42 and that's 10ah of.playtime. You could.easily.mount.charging jacks for each battery in the back so you don't even need to take them out of pinhead.

#5

Yep, 2 to start with I think.

#6

Cool beans , I think I will do 4 when I do it since my robot is running a onboard PC.

#7

I would love to use these batteries but my bot will back into charging station and charge while still running.

#8

It could but I recommend the bot mostly shutdown or at least suspend most operations because any juice used is juice that the battery does not get. The charger your using must be capable of maintain ing voltage even with your equipment on. It can be done though.

#9

can easy make a balance charger,whats needed is a constant current source ,like LM317 adustable regulator set up in current mode,and constant voltage using LM317 set for the correct voltage
plus a balance board from ebay ,all well under $15 total
CAN NOT use gel cell charger its only constant voltage out
drawback on using LI-PO batteries is can charge them many times and have a short life cycle ,cost is about double
but other then that a great battery to be used
they mostly used in RC cars alot
and you really dont need to remove it,easy relay disconnect charging circuit can do the job