Battery Adapter, Typhoon H, DIY

KEITH KUHN · Oct 13, 2019

Danny J said:
Just some battery/flight duration RIP (Random Information Particles): I've had my Typhoon H (with RealSense installed) for around 14 months. All my flying so far has been with one of the three Yuneec OEM 5400mAH batteries. I had always set myself up to return back to land when I got the LOW BATTERY alert. Depending on the winds, altitude and maneuvering the flight durations ranged from 10 to 13 minutes. This didn't seem to be a good duration number so I ran some flight tests where I would return "home" at the LOW BATT warning but rather than land,

Upon arriving back at the landing area, I flew around the vicinity of the landing pad at around 50-foot altitudes. More LOW BATTERY alerts would pop up but I kept an eye on the voltage on-screen. It kept going and going. When the voltage dropped under 14.0 volts, I moved the H over the landing area and down to 15 or 20 feet. It kept flying and flying. It finally proceded to initiate its AUTO-LAND sequence at 13.3 volts. The flight had lasted 17+ minutes. I repeated this test with the other batteries (still the 5400 mAH) and got 16+ minutes and 18 minutes! I have newfound confidence to fly well beyond the LOW BATT warnings the system conservatively provides. The additional 3 to 5 minutes of flight time makes the entire experience a bit less "urgent" and yields more opportunities for setting up beautifully framed images and videos.

There are quite a few variables that affect the flight duration and even flying techniques that do not put high current demands on the battery. For instance, I've noticed that when the batteries are cool the voltage drop with high current maneuvering will often trigger the LOW BATTERY warning. By limiting the current draw in the first 2 minutes while the battery pack warms up then allows the cells to meet the high current demands without the "inefficient" voltage drop. I have also noted that rapid descent from altitude significantly reduces the current draw and allows the cells to "recover" for improved duration. A third technique involves winds aloft and planning ahead for penetrations into the wind/upwind. The free version of the handy smartphone app, UAV FORECAST, has a WIND PROFILE feature which shows wind speed and direction in increments up to 5,000 feet AGL. Temperature inversions and strong horizontal barometric pressure gradients can produce winds at altitude that are significantly stronger and from a different direction than at the ground. For example, as I write this the local surface winds just before sunset is around 3 to 5 mph from the W. At 500 feet AGL the wind is 20 mph with gusts to 54 mph! and from the SW. Horizontal flight against the wind tonight should be done as low as possible - treetop height - where the wind is still just 10 mph with possible gusts to 24 mph. Another handy app is the free version of AVIA WEATHER which provides visibility/temp/barometer/cloudbase for all the local reporting airports.

When it went into Auto land, Did you notice any toilet bowling ?

Steve Carr · Oct 13, 2019

Danny J said:
When the voltage dropped under 14.0 volts, I moved the H over the landing area and down to 15 or 20 feet. It kept flying and flying. It finally proceded to initiate its AUTO-LAND sequence at 13.3 volts.

Nice to try it once, but repeating this could very well end badly for you. Drawing the battery down that low will shorten the life of the battery. In addition, at the point where one cell becomes weaker the voltage can take a sudden drop and not allow time for an auto landing or a manual landing. The motors will just shut down. The glide path is vertical. I've seen this "sudden death" syndrome in many telemetry files where the batt voltage takes a dive a second before the aircraft also dives. You may wish to start monitoring internal resistance of the batts.

Your observations regarding wind and high speed maneuvers are spot on. A hover in a 20 mph wind means the aircraft is actually flying at 20 mph. Conservative flying and paying attention to wind speed and direction yields much better flight times.
I've found it interesting the LiHV batteries seem to do much better in cold temps than the Lipos.

KEITH KUHN · Oct 14, 2019

Steve Carr said:
Nice to try it once, but repeating this could very well end badly for you. Drawing the battery down that low will shorten the life of the battery. In addition, at the point where one cell becomes weaker the voltage can take a sudden drop and not allow time for an auto landing or a manual landing. The motors will just shut down. The glide path is vertical. I've seen this "sudden death" syndrome in many telemetry files where the batt voltage takes a dive a second before the aircraft also dives. You may wish to start monitoring internal resistance of the batts.

Your observations regarding wind and high speed maneuvers are spot on. A hover in a 20 mph wind means the aircraft is actually flying at 20 mph. Conservative flying and paying attention to wind speed and direction yields much better flight times.
I've found it interesting the LiHV batteries seem to do much better in cold temps than the Lipos.

What does LiHV. Mean ?

Mrgs1 · Oct 14, 2019

KEITH KUHN said:
What does LiHV. Mean ?

LiHV (or HVLi) stands for “High Voltage Lithium Polymer”. It's a similar to LiPo battery but allows you charge it up to 4.35V per cell safely. When you charge LiHV batteries like standard LiPo to only 4.20V per cell, they perform pretty much similar.

KEITH KUHN · Oct 14, 2019

Mrgs1 said:
LiHV (or HVLi) stands for “High Voltage Lithium Polymer”. It's a similar to LiPo battery but allows you charge it up to 4.35V per cell safely. When you charge LiHV batteries like standard LiPo to only 4.20V per cell, they perform pretty much similar.

Do you recommend them over OEM Batteries
For the TY -H. ?

KEITH KUHN · Oct 14, 2019

KEITH KUHN said:
Do you recommend them over OEM Batteries
For the TY -H. ?m

Also do you need to use any type of battery adapters. Or different
Cables.
Keith

Mrgs1 · Oct 14, 2019

KEITH KUHN said:
Do you recommend them over OEM Batteries
For the TY -H. ?

Personally I would use just Lipo batteries, Lihv charge at a different rate and higher voltage, I believe vigilance when using to make sure you don't discharge too low, and they probably don't last as long as Lipo batteries, and cost more.