There's a free application for your Android Smartphone/Tablet that allows you to look at most all the information that the car's computer system(s) know about in real time. You need an appropriate Android based tablet or phone with Bluetooth and a Bluetooth ODBII connector that plugs into your car. Data includes individual cell voltages and temps, yes 88 of them at once, so you can see how your battery pack is doing. Current usage and watt/hr/mile and charge history and more other data then you'll ever have use for.
This might seem like overkill, but being able to peek into your battery pack while the car is running can give you way more information about pack health than even the dealer can get. Since most of the dealers don't have good battery testing facilities and are not doing anything significant in terms of yearly maintenance anyway (not to mention that the idiots keep sending coupons for oil changes - etc.), this becomes doubly important.
One other important thing is it can show you the actual battery capacity% so you can gauge how much (if any) your pack had degraded. The LEAF actually has a (somewhat crude) dash display for that but even there it's worth looking at the details. This is especially important if looking at a used one. LeafSpy is the equivalent app for the LEAF. See below.
Issues: There is no 'Miles' mode. KM only (you can do the math.) We couldn't get it to work with tablets that have the more square-ish (4:3) displays. The ones with a 16:9 worked: 848x480 and 1280x720 worked but 1024x768 didn't. The rare tablet with a RockChip processor didn't work either, though that may be version dependent. YMMV as usual.
The ScanTool MX adapter has the additional advantage that it has a 'sleep' mode so it won't drain your battery. If you're using one of the ELM327 ones you should unplug it after use.
Plug in, Turn on and Sync up! No, it won't damage your car's computer, well, unless you deliver a big static charge zap when you plug it in. Watch out for that on cold dry days...
Leaf Spy Info at MyNissanLeaf.com which is a site you should certainly be looking at if you're a Leaf owner. The interesting thing about this is that it was built from the ground up to use the ELM327 el-cheapo Bluetooth ODBII adapters you can get from Amazon and various Chinese vendors for $20 and under. The exact same ones that won't work with CaniOn. This makes the Leaf battery app 'Lite' a somewhat cheaper alternative than the iMiEV focused stuff.
If you're going to buy a used EV, I highly recommend having one of these this apps and adapter so you can check out the battery pack under all conditions like: Low battery level (mostly discharged, near 'Turtle' mode) under load. Monitor during charge. Look at temperatures during charge equalization as you approach 100%. Battery variance throughout the process, and capacity remaining once charged. Yes this will take -hours- but buying a car with bad cell(s) would be an even bigger bummer. You can also look at the charge history using the app. Like almost anything cool, functional and low cost, it's not available for iPhone. You'll be in the odd situation of knowing more about the used car you're looking at than any buyer of a 'regular' car would know...
