EM3ev 72V (20S10P) Rectangle Battery Pack
EM3ev 72V (20S10P) Rectangle Battery Pack may take some time to be built. Due to a large amount of recent battery orders, if we do not have a particular battery pack already built in stock, it will currently take us 10 to 14 days to manufacture it (27/03/17).
Em3ev battery packs include (patented) safety features that you will not find elsewhere (on any Ebike Battery Pack that we are aware of). Our stand out battery pack features are the facts that every single cell in the battery is fused. The signal wires are also fused. This is in addition to the normal battery management system (BMS). The BMS protects the battery against over-charge, excessive charge/discharge current and also balancing.
Our rectangular battery packs are housed in a very robust plastic case. This not only provides serious mechanical protection, but is also water-resistant. We build battery packs (and design/manufacture most of the key component parts on our own high-tech machines). We build our own battery packs, as we want to do things right, we want to do things safe, we want to innovate and because we can.
EM3ev packs are always conservatively/accurately rated, which will help to ensure our packs provide a long and reliable service life. On top of all this, we stand behind our products (1 year warranty) and WE WILL fix any issues that occur (with minimum inconvenience, no cost to the customer and no we do not ask customers to return parts to China!). Here at EM3ev, we are not about hype, spin and self-promotion, our reputation was built the old fashioned way, by happy/satisfied customers.
EM3ev 72V (20S10P) Rectangle Battery Pack: BMS and Discharge Info
Our 20S BMS is rated for 80A continuous discharge current and ~120A peak discharge current. We would recommend the cells be ran at roughly 50% of their max continuous ratings. Of course they can provide the full discharge, but there can be voltage sag and reduced capacity if this is done.
For the 25R cells this means a recommended max discharge current of approx. 100A and ~74A max discharged current for the 30Q cells.
EM3ev 72V (20S10P) Rectangle Battery Pack: Cell Types
We offer various Samsung and LG cell types, in addition to the standard ICR18650-22 (NCM cell, 3C rated, approximately 2.1Ah) cell. These new cell types are the High Energy INR18650-33G (NCA Cell, 3C Max rated cell, with approx. 3.1Ah nominal Capacity) and LG MJ1 (NCA, 3C Max, ~3.40Ah). There is also the High Power cells, the INR18650-25R and INR18650-30Q. These are NCA type cells, ~8C rated with Capacity of approximately 2.45Ah (25R) and ~5C rated and capacity of 2.95Ah for the 30Q cell. Regardless of the cell type used, the dimensions of the pack are unchanged.
EM3ev 72V (20S10P) Rectangle Battery Pack: Pre-Charge
When the customer orders a battery with a kit we will make the controller to battery connections plug. This includes a Pre-Charge. We will supply a matching tail which should be linked to your existing controller if a battery is purchased without a controller. We use the XT90-S pre-charge connector. It is essential a Pre-Charge is used when connecting to the controller to avoid the large spark that occurs without such a system. This will avoid issues with connectors and the Battery BMS. Various optional chargers are offered.
EM3ev 72V (20S10P) Rectangle Battery Pack Specs:
- PPTC thermal fuses used on all signal wires. If a fault were to ever occur on any of the small balance wires which run around the battery pack, the fuse simply shuts down the connection and keeps everything safe. Once the fault condition is removed, function returns to normal.
- We conservatively rate the cells as 2.45Ah (SDI, 25R), 2.10Ah (SDI, 22P), 3.10Ah (SDI, 33G), 3.40Ah (LG MJ1), and 2.95Ah (SDI, 30Q). Like with any Li Ion type battery, best long term performance is obtained by not using all of the available capacity all of the time.
- Energy Density of 150Whrs plus for finished pack.
EM3ev 72V (20S10P) Rectangle Battery Pack Cycle Life and Charging
- Cycle Life estimated at 500-700 cycles (to 80% Retained) with 100% Charge and 100% discharge cycles. Cycle life is extended (possibly doubled) by charging to 90% and limiting discharge to 90%. So if you use 80% of the available capacity (most, but not all of the time). We make it easy to control the Charge voltage with our switching charger. To accurately limit discharge the Cycle Analyst is a great tool. Using continuous High Discharge Rates over the recommended levels will cause cell heating and can shorten cycle life.
- Charge Voltage of 84V for 100% charger, 82V for 90% and 76V for 50% charge. (Our NCM 3A chargers include a switch to charge to 100%, 90% and 50%).
- Maximum Charge Current 12A max (BMS limited).
EM3ev 72V (20S10P) Rectangle Battery Pack: Weight and Dimensions
- Dimensions: ~195*230*140mm
- Weight: 11kg (25R and 30P)